nextcloud CVE Vulnerabilities & Metrics

Nextcloud Server is a self hosted personal cloud system. Under certain conditions the password of a user was stored unencrypted in the session data. The session data is encrypted before being saved in the session storage (Redis or disk), but it would allow a malicious process that gains access to the memory of the PHP process, to get access to the cleartext password of the user. It is recommended that the Nextcloud Server is upgraded to 28.0.12, 29.0.9 or 30.0.2.

Nextcloud Server is a self hosted personal cloud system. MD5 hashes were used to check background jobs for their uniqueness. This increased the chances of a background job with arguments falsely being identified as already existing and not be queued for execution. By changing the Hash to SHA256 the probability was heavily decreased. It is recommended that the Nextcloud Server is upgraded to 28.0.10, 29.0.7 or 30.0.0.

Nextcloud Server is a self hosted personal cloud system. The OAuth2 client secrets were stored in a recoverable way, so that an attacker that got access to a backup of the database and the Nextcloud config file, would be able to decrypt them. It is recommended that the Nextcloud Server is upgraded to 28.0.10 or 29.0.7 and Nextcloud Enterprise Server is upgraded to 27.1.11.8, 28.0.10 or 29.0.7.

Nextcloud Server is a self hosted personal cloud system. After an attacker got access to the session of a user or administrator, the attacker would be able to create, change or delete external storages without having to confirm the password. It is recommended that the Nextcloud Server is upgraded to 28.0.12, 29.0.9 or 30.0.2.

Nextcloud Server is a self hosted personal cloud system. After storing "Global credentials" on the server, the API returns them and adds them into the frontend again, allowing to read them in plain text when an attacker already has access to an active session of a user. It is recommended that the Nextcloud Server is upgraded to 28.0.11, 29.0.8 or 30.0.1 and Nextcloud Enterprise Server is upgraded to 25.0.13.13, 26.0.13.9, 27.1.11.9, 28.0.11, 29.0.8 or 30.0.1.

Nextcloud Server is a self hosted personal cloud system. When a server is configured to only allow sharing with users that are in ones own groups, after a user was removed from a group, previously shared items were not unshared. It is recommended that the Nextcloud Server is upgraded to 22.2.11 or 23.0.11 or 24.0.6 and Nextcloud Enterprise Server is upgraded to 22.2.11 or 23.0.11 or 24.0.6.

In Nextcloud Desktop Client 3.13.1 through 3.13.3 on Linux, synchronized files (between the server and client) may become world writable or world readable. This is fixed in 3.13.4.

Nextcloud Server is a self hosted personal cloud system. Private shared calendar events' recurrence exceptions can be read by sharees. It is recommended that the Nextcloud Server is upgraded to 27.1.10 or 28.0.6 or 29.0.1 and that the Nextcloud Enterprise Server is upgraded to 27.1.10 or 28.0.6 or 29.0.1.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. A code injection in Nextcloud Desktop Client for macOS allowed to load arbitrary code when starting the client with DYLD_INSERT_LIBRARIES set in the enviroment. It is recommended that the Nextcloud Desktop client is upgraded to 3.12.0.

Nextcloud Server is a self hosted personal cloud system. A malicious user was able to send delete requests for old versions of files they only got shared with read permissions. It is recommended that the Nextcloud Server is upgraded to 26.0.12 or 27.1.7 or 28.0.3 and that the Nextcloud Enterprise Server is upgraded to 26.0.12 or 27.1.7 or 28.0.3.

Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. A user with access to a deck board was able to access comments and attachments of already deleted cards. It is recommended that the Nextcloud Deck app is upgraded to 1.6.6 or 1.7.5 or 1.8.7 or 1.9.6 or 1.11.3 or 1.12.1.

Nextcloud Server is a self hosted personal cloud system. A recipient of a share with read&share permissions could reshare the item with more permissions. It is recommended that the Nextcloud Server is upgraded to 26.0.13 or 27.1.8 or 28.0.4 and that the Nextcloud Enterprise Server is upgraded to 26.0.13 or 27.1.8 or 28.0.4.

The Nextcloud Notes app is a distraction free notes taking app for Nextcloud. If an attacker managed to share a folder called `Notes/` with a newly created user before they logged in, the Notes app would use that folder store the personal notes. It is recommended that the Nextcloud Notes app is upgraded to 4.9.3.

Nextcloud Calendar is a calendar app for Nextcloud. Authenticated users could create an event with manipulated attachment data leading to a bad redirect for participants when clicked. It is recommended that the Nextcloud Calendar App is upgraded to 4.6.8 or 4.7.2.

Nextcloud Server is a self hosted personal cloud system. An attacker with read-only access to a file is able to restore older versions of a document when the files_versions app is enabled. It is recommended that the Nextcloud Server is upgraded to 26.0.12, 27.1.7 or 28.0.3 and that the Nextcloud Enterprise Server is upgraded to 23.0.12.16, 24.0.12.12, 25.0.13.6, 26.0.12, 27.1.7 or 28.0.3.

Nextcloud Photos is a photo management app. Users can remove photos from the album of registered users. It is recommended that the Nextcloud Server is upgraded to 25.0.7 or 26.0.2 and the Nextcloud Enterprise Server is upgraded to 25.0.7 or 26.0.2.

Nextcloud files Zip app is a tool to create zip archives from one or multiple files from within Nextcloud. In affected versions users can download "view-only" files by zipping the complete folder. It is recommended that the Files ZIP app is upgraded to 1.2.1, 1.4.1, or 1.5.0. Users unable to upgrade should disable the file zip app.

Nextcloud guests app is a utility to create guest users which can only see files shared with them. In affected versions users were able to load the first page of apps they were actually not allowed to access. Depending on the selection of apps installed this may present a permissions bypass. It is recommended that the Guests app is upgraded to 2.4.1, 2.5.1 or 3.0.1. There are no known workarounds for this vulnerability.

Nextcloud guests app is a utility to create guest users which can only see files shared with them. In affected versions users could change the allowed list of apps, allowing them to use apps that were not intended to be used. It is recommended that the Guests app is upgraded to 2.4.1, 2.5.1 or 3.0.1. There are no known workarounds for this vulnerability.

Nextcloud server is a self hosted personal cloud system. In affected versions OAuth codes did not expire. When an attacker would get access to an authorization code they could authenticate at any time using the code. As of version 28.0.0 OAuth codes are invalidated after 10 minutes and will no longer be authenticated. To exploit this vulnerability an attacker would need to intercept an OAuth code from a user session. It is recommended that the Nextcloud Server is upgraded to 28.0.0. There are no known workarounds for this vulnerability.

Nextcloud User Saml is an app for authenticating Nextcloud users using SAML. In affected versions users can be given a link to the Nextcloud server and end up on a uncontrolled thirdparty server. It is recommended that the User Saml app is upgraded to version 5.1.5, 5.2.5, or 6.0.1. There are no known workarounds for this issue.

Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. In affected versions users could be tricked into executing malicious code that would execute in their browser via HTML sent as a comment. It is recommended that the Nextcloud Deck is upgraded to version 1.9.5 or 1.11.2. There are no known workarounds for this vulnerability.

Nextcloud Global Site Selector is a tool which allows you to run multiple small Nextcloud instances and redirect users to the right server. A problem in the password verification method allows an attacker to authenticate as another user. It is recommended that the Nextcloud Global Site Selector is upgraded to version 1.4.1, 2.1.2, 2.3.4 or 2.4.5. There are no known workarounds for this issue.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server prior to versions 26.0.9 and 27.1.4; as well as Nextcloud Enterprise Server prior to versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4; when a (reverse) proxy is configured as trusted proxy the server could be tricked into reading a wrong remote address for an attacker, allowing them executing authentication attempts than intended. Nextcloud Server versions 26.0.9 and 27.1.4 and Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server prior to versions 26.0.9 and 27.1.4; as well as Nextcloud Enterprise Server prior to versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4; when an attacker manages to get access to an active session of another user via another way, they could delete and modify workflows by sending calls directly to the API bypassing the password confirmation shown in the UI. Nextcloud Server versions 26.0.9 and 27.1.4 and Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 contain a patch for this issue. No known workarounds are available.

The Nextcloud iOS Files app allows users of iOS to interact with Nextcloud, a self-hosted productivity platform. Prior to version 4.9.2, the application can be used without providing the 4 digit PIN code. Nextcloud iOS Files app should be upgraded to 4.9.2 to receive the patch. No known workarounds are available.

Nextcloud/Cloud is a calendar app for Nextcloud. An attacker can gain access to stacktrace and internal paths of the server when generating an exception while editing a calendar appointment. It is recommended that the Nextcloud Calendar app is upgraded to 4.5.3

Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Starting in version 1.13.0 and prior to version 2.2.8 and 3.3.0, an attacker can use an unprotected endpoint in the Mail app to perform a SSRF attack. Nextcloud Mail app versions 2.2.8 and 3.3.0 contain a patch for this issue. As a workaround, disable the mail app.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Server and starting in version 22.0.0 and prior to versions 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Enterprise Server, the DNS pin middleware was vulnerable to DNS rebinding allowing an attacker to perform SSRF as a final result. Nextcloud Server 25.0.11, 26.0.6, and 27.1.0 and Nextcloud Enterprise Server 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 contain patches for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Server and Nextcloud Enterprise Server, when the log level was set to debug, the user_ldap app logged user passwords in plaintext into the log file. If the log file was then leaked or shared in any way the users' passwords would be leaked. Nextcloud Server and Nextcloud Enterprise Server versions 25.0.11, 26.0.6, and 27.1.0 contain a patch for this issue. As a workaround, change config setting `loglevel` to `1` or higher (should always be higher than 1 in production environments).

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Server and starting in version 22.0.0 and prior to versions 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Enterprise Server, an attacker could enable and disable the birthday calendar for any user on the same server. Nextcloud Server 25.0.11, 26.0.6, and 27.1.0 and Nextcloud Enterprise Server 22.2.10.16, 23.0.12.11, 24.0.12.7, 25.0.11, 26.0.6, and 27.1.0 contain patches for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.11, 26.0.6, and 27.1.0 of Nextcloud Server and Nextcloud Enterprise Server, admins can change authentication details of user configured external storage. Nextcloud Server and Nextcloud Enterprise Server versions 25.0.11, 26.0.6, and 27.1.0 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.13, 26.0.8, and 27.1.3 of Nextcloud Server and Nextcloud Enterprise Server, when a user is tricked into copy pasting HTML code without markup (Ctrl+Shift+V) the markup will actually render. Nextcloud Server and Nextcloud Enterprise Server versions 25.0.13, 26.0.8, and 27.1.3 contain a fix for this issue. As a workaround, disable app text.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.13, 26.0.8, and 27.1.3 of Nextcloud Server and Nextcloud Enterprise Server, an attacker could insert links into circles name that would be opened when clicking the circle name in a search filter. Nextcloud Server and Nextcloud Enterprise Server versions 25.0.13, 26.0.8, and 27.1.3 contain a fix for this issue. As a workaround, disable app circles.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.13, 26.0.8, and 27.1.3 of Nextcloud Server and starting in version 20.0.0 and prior to versions 20.0.14.16, 21.0.9.13, 22.2.10.15, 23.0.12.12, 24.0.12.8, 25.0.13, 26.0.8, and 27.1.3 of Nextcloud Enterprise Server, a malicious user could update any personal or global external storage, making them inaccessible for everyone else as well. Nextcloud Server 25.0.13, 26.0.8, and 27.1.3 and Nextcloud Enterprise Server is upgraded to 20.0.14.16, 21.0.9.13, 22.2.10.15, 23.0.12.12, 24.0.12.8, 25.0.13, 26.0.8, and 27.1.3 contain a patch for this issue. As a workaround, disable app files_external. This workaround also makes the external storage inaccessible but retains the configurations until a patched version has been deployed.

Nextcloud calendar is a calendar app for the Nextcloud server platform. Due to missing precondition checks the server was trying to validate strings of any length as email addresses even when megabytes of data were provided, eventually making the server busy and unresponsive. It is recommended that the Nextcloud Calendar app is upgraded to 4.4.4. The only workaround for users unable to upgrade is to disable the calendar app.

Nextcloud talk is a chat module for the Nextcloud server platform. In affected versions brute force protection of public talk conversation passwords can be bypassed, as there was an endpoint validating the conversation password without registering bruteforce attempts. It is recommended that the Nextcloud Talk app is upgraded to 15.0.8, 16.0.6 or 17.1.1. There are no known workarounds for this vulnerability.

Nextcloud mail is an email app for the Nextcloud home server platform. In affected versions a missing check of origin, target and cookies allows for an attacker to abuse the proxy endpoint to denial of service a third server. It is recommended that the Nextcloud Mail is upgraded to 2.2.8 or 3.3.0. There are no known workarounds for this vulnerability.

Nextcloud server is an open source home cloud platform. Affected versions of Nextcloud stored OAuth2 tokens in plaintext which allows an attacker who has gained access to the server to potentially elevate their privilege. This issue has been addressed and users are recommended to upgrade their Nextcloud Server to version 25.0.8, 26.0.3 or 27.0.1. There are no known workarounds for this vulnerability.

Nextcloud is an open source home cloud server. When Memcached is used as `memcache.distributed` the rate limiting in Nextcloud Server could be reset unexpectedly resetting the rate count earlier than intended. Users are advised to upgrade to versions 25.0.11, 26.0.6 or 27.1.0. Users unable to upgrade should change their config setting `memcache.distributed` to `\OC\Memcache\Redis` and install Redis instead of Memcached.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server starting with 25.0.0 and prior to 25.09 and 26.04; as well as Nextcloud Enterprise Server starting with 22.0.0 and prior to 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, and 26.0.4; missing protection allows an attacker to brute force passwords on the WebDAV API. Nextcloud Server 25.0.9 and 26.0.4 and Nextcloud Enterprise Server 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, and 26.0.4 contain patches for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 20.0.0 and prior to versions 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, a missing password confirmation allowed an attacker, after successfully stealing a session from a logged in user, to create app passwords for the victim. Nextcloud server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 19.0.0 and prior to versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, a malicious user could delete any personal or global external storage, making them inaccessible for everyone else as well. Nextcloud server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. As a workaround, disable app files_external. This also makes the external storage inaccessible but retains the configurations until a patched version has been deployed.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 24.0.4 and prior to versions 25.0.9, 26.0.4, and 27.0.1, when a folder with images or an image was shared without download permissions, the user could add the image inline into a text file and download it. Nextcloud Server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 25.0.0 and prior to versions 25.0.9, 26.0.4, and 27.0.1, unauthenticated users could send a DAV request which reveals whether a calendar or an address book with the given identifier exists for the victim. Nextcloud Server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 22.0.0 and prior to versions 22.2.10.13, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, missing protection allows an attacker to brute force the client secrets of configured OAuth2 clients. Nextcloud Server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 22.2.10.13, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Talk Android allows users to place video and audio calls through Nextcloud on Android. Prior to version 17.0.0, an unprotected intend allowed malicious third party apps to trick the Talk Android app into writing files outside of its intended cache directory. Nextcloud Talk Android version 17.0.0 has a patch for this issue. No known workarounds are available.

Notes is a note-taking app for Nextcloud, an open-source cloud platform. Starting in version 4.4.0 and prior to version 4.8.0, when creating a note file with HTML, the content is rendered in the preview instead of the file being offered to download. Nextcloud Notes app version 4.8.0 contains a patch for the issue. No known workarounds are available.

user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, an attacker that obtained at least read access to a snapshot of the database can impersonate the Nextcloud server towards linked servers. user_oidc 1.3.3 contains a patch. No known workarounds are available.

user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, missing verification of the issuer would have allowed an attacker to perform a man-in-the-middle attack returning corrupted or known token they also have access to. user_oidc 1.3.3 contains a patch. No known workarounds are available.

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 22.0.0 and prior to versions 22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3, and 27.0.1, a user can access files inside a subfolder of a groupfolder accessible to them, even if advanced permissions would block access to the subfolder. Nextcloud Server versions 25.0.8, 26.0.3, and 27.0.1 and Nextcloud Enterprise Server versions 22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3, and 27.0.1 contain a patch for this issue. No known workarounds are available.

Nextcloud Server is a space for data storage on Nextcloud, a self-hosted productivity playform. In NextCloud Server versions 25.0.0 until 25.0.7 and 26.0.0 until 26.0.2 and Nextcloud Enterprise Server versions 19.0.0 until 19.0.13.9, 20.0.0 until 20.0.14.14, 21.0.0 until 21.0.9.12, 22.0.0 until 22.2.10.12, 23.0.0 until 23.0.12.7, 24.0.0 until 24.0.12.2, 25.0.0 until 25.0.7, and 26.0.0 until 26.0.2, a user could use this functionality to get access to the login credentials of another user and take over their account. This issue has been patched in Nextcloud Server versions 25.0.7 and 26.0.2 and NextCloud Enterprise Server versions 19.0.13.9, 20.0.14.14, 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7, and 26.0.2. Three workarounds are available. Disable app files_external. Change config setting "Allow users to mount external storage" to disabled in "Administration" > "External storage" settings `…/index.php/settings/admin/externalstorages`. Change config setting to disallow users to create external storages in "Administration" > "External storage" settings `…/index.php/settings/admin/externalstorages` with the types FTP, Nextcloud, SFTP, and/or WebDAV.

NextCloud Server and NextCloud Enterprise Server provide file storage for Nextcloud, a self-hosted productivity platform. In NextCloud Server versions 25.0.0 until 25.0.7 and 26.0.0 until 26.0.2 and Nextcloud Enterprise Server versions 21.0.0 until 21.0.9.12, 22.0.0 until 22.2.10.12, 23.0.0 until 23.0.12.7, 24.0.0 until 24.0.12.2, 25.0.0 until 25.0.7, and 26.0.0 until 26.0.2, when two server are registered as trusted servers for each other and successfully exchanged the share secrets, the malicious server could modify or delete VCards in the system addressbook on the origin server. This would impact the available and shown information in certain places, such as the user search and avatar menu. If a manipulated user modifies their own data in the personal settings the entry is fixed again. Nextcloud Server n 25.0.7 and 26.0.2 and Nextcloud Enterprise Server 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7, and 26.0.2 contain a patch for this issue. A workaround is available. Remove all trusted servers in the "Administration" > "Sharing" settings `…/index.php/settings/admin/sharing`. Afterwards, trigger a recreation of the local system addressbook with the following `occ dav:sync-system-addressbook`.

Nextcloud End-to-end encryption app provides all the necessary APIs to implement End-to-End encryption on the client side. By providing an invalid meta data file, an attacker can make previously dropped files inaccessible. It is recommended that the Nextcloud End-to-end encryption app is upgraded to version 1.12.4 that contains the fix.

NextCloud Server and NextCloud Enterprise Server provide file storage for Nextcloud, a self-hosted productivity platform. In NextCloud Server versions 25.0.0 until 25.0.7 and 26.0.0 until 26.0.2 and Nextcloud Enterprise Server versions 21.0.0 until 21.0.9.12, 22.0.0 until 22.2.10.12, 23.0.0 until 23.0.12.7, 24.0.0 until 24.0.12.2, 25.0.0 until 25.0.7, and 26.0.0 until 26.0.2, an attacker can bruteforce the password reset links. Nextcloud Server n 25.0.7 and 26.0.2 and Nextcloud Enterprise Server 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7, and 26.0.2 contain a patch for this issue. No known workarounds are available.

NextCloud Server and NextCloud Enterprise Server provide file storage for Nextcloud, a self-hosted productivity platform. Starting in version 26.0.0 and prior to version 26.0.2, an attacker could supply a URL that redirects an unsuspecting victim from a legitimate domain to an attacker's site. Nextcloud Server and Nextcloud Enterprise Server 26.0.2 contain a patch for this issue. No known workarounds are available.

Nextcloud Server is a data storage system for Nextcloud, a self-hosted productivity platform. When multiple requests are sent in parallel, all of them were executed even if the amount of faulty requests succeeded the limit by the time the response was sent to the client. This allowed someone to send as many requests the server could handle in parallel to bruteforce protected details instead of the configured limit, default 8. Nextcloud Server versions 25.0.7 and 26.0.2 and Nextcloud Enterprise Server versions 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7 and 26.0.2 contain patches for this issue.

Calendar app for Nextcloud easily sync events from various devices with your Nextcloud. Some internal paths of the website are disclosed when the SMTP server is unavailable. It is recommended that the Calendar app is updated to 3.5.5 or 4.2.3

Nextcloud Mail is a mail app in Nextcloud. A blind SSRF attack allowed to send GET requests to services running in the same web server. It is recommended that the Mail app is update to version 3.02, 2.2.5 or 1.15.3.

Nextcloud server is an open source personal cloud implementation. Missing brute-force protection on the WebDAV endpoints via the basic auth header allowed to brute-force user credentials when the provided user name was not an email address. Users from version 24.0.0 onward are affected. This issue has been addressed in releases 24.0.11, 25.0.5 and 26.0.0. Users are advised to upgrade. There are no known workarounds for this vulnerability.

NextCloud Cookbook is a recipe library app. Prior to commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch, the `pull-checks.yml` workflow is vulnerable to command injection attacks because of using an untrusted `github.head_ref` field. The `github.head_ref` value is an attacker-controlled value. Assigning the value to `zzz";echo${IFS}"hello";#` can lead to command injection. Since the permission is not restricted, the attacker has a write-access to the repository. This issue is fixed in commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch. There is no risk for the user of the app within the NextCloud server. This only affects the main repository and possible forks of it. Those who have forked the NextCloud Cookbook repository should make sure their forks are on the latest version to prevent code injection attacks and similar.

Nextcloud server provides a home for data. A regression in the session handling between Nextcloud Server and the Nextcloud Text app prevented a correct destruction of the session on logout if cookies were not cleared manually. After successfully authenticating with any other account the previous session would be continued and the attacker would be authenticated as the previously logged in user. It is recommended that the Nextcloud Server is upgraded to 25.0.6 or 26.0.1.

user_oidc app is an OpenID Connect user backend for Nextcloud. Authentication can be broken/bypassed in user_oidc app. It is recommended that the Nextcloud user_oidc app is upgraded to 1.3.2

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. In Nextcloud Server 24.0.0 prior to 24.0.11 and 25.0.0 prior to 25.0.5; as well as Nextcloud Server Enterprise 23.0.0 prior to 23.0.12.6, 24.0.0 prior to 24.0.11, and 25.0.0 prior to 25.0.5; an attacker is not restricted in verifying passwords of share links so they can just start brute forcing the password. Nextcloud Server 24.0.11 and 25.0.5 and Nextcloud Enterprise Server 23.0.12.6, 24.0.11, and 25.0.5 contain a fix for this issue. No known workarounds are available.

Nextcloud Talk is a chat, video & audio call extension for Nextcloud. In affected versions a user that was added later to a conversation can use this information to get access to data that was deleted before they were added to the conversation. This issue has been patched in version 15.0.5 and it is recommended that users upgrad to 15.0.5. There are no known workarounds for this issue.

Nextcloud is a personal home server system. Depending on the set up tags and other workflows this issue can be used to limit access of others or being able to grant them access when there are system tag based files access control or files retention rules. It is recommended that the Nextcloud Server is upgraded to 24.0.11 or 25.0.5, the Nextcloud Enterprise Server to 21.0.9.11, 22.2.10.11, 23.0.12.6, 24.0.11 or 25.0.5, and the Nextcloud Files automated tagging app to 1.11.1, 1.12.1, 1.13.1, 1.14.2, 1.15.3 or 1.16.1. Users unable to upgrade should disable all workflow related apps. Users are advised to upgrade.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server. Starting with version 3.0.0 and prior to version 3.7.0, by trusting that the server will return a certificate that belongs to the keypair of the user, a malicious server could get the desktop client to encrypt files with a key known to the attacker. This issue is fixed in Nextcloud Desktop 3.7.0. No known workarounds are available.

Nextcloud is an open-source productivity platform. In Nextcloud Desktop client 3.0.0 until 3.8.0, Nextcloud Android app 3.13.0 until 3.25.0, and Nextcloud iOS app 3.0.5 until 4.8.0, a malicious server administrator can gain full access to an end-to-end encrypted folder. They can decrypt files, recover the folder structure and add new files.​ This issue is fixed in Nextcloud Desktop 3.8.0, Nextcloud Android 3.25.0, and Nextcloud iOS 4.8.0. No known workarounds are available.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server. Starting with version 3.0.0 and prior to version 3.6.5, a malicious server administrator can gain full access to an end-to-end encrypted folder. They can decrypt files, recover the folder structure, and add new files.​ Users should upgrade the Nextcloud Desktop client to 3.6.5 to receive a patch. No known workarounds are available.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server. Starting with version 3.0.0 and prior to version 3.6.5, a malicious server administrator can recover and modify the contents of end-to-end encrypted files. Users should upgrade the Nextcloud Desktop client to 3.6.5 to receive a patch. No known workarounds are available.

user_oidc is the OIDC connect user backend for Nextcloud, an open source collaboration platform. A vulnerability in versions 1.0.0 until 1.3.0 effectively allowed an attacker to bypass the state protection as they could just copy the expected state token from the first request to their second request. Users should upgrade user_oidc to 1.3.0 to receive a patch for the issue. No known workarounds are available.

Nextcloud Server is an open source personal cloud server. Nextcloud Server 24.0.0 until 24.0.6 and 25.0.0 until 25.0.4, as well as Nextcloud Enterprise Server 23.0.0 until 23.0.11, 24.0.0 until 24.0.6, and 25.0.0 until 25.0.4, have an information disclosure vulnerability. A user was able to get the full data directory path of the Nextcloud server from an API endpoint. By itself this information is not problematic as it can also be guessed for most common setups, but it could speed up other unknown attacks in the future if the information is known. Nextcloud Server 24.0.6 and 25.0.4 and Nextcloud Enterprise Server 23.0.11, 24.0.6, and 25.0.4 contain patches for this issue. There are no known workarounds.

Nextcloud talk is a video & audio conferencing app for Nextcloud. In affected versions the talk app does not properly filter access to a conversations member list. As a result an attacker could use this vulnerability to gain information about the members of a Talk conversation, even if they themselves are not members. It is recommended that the Nextcloud Talk is upgraded to 14.0.9 or 15.0.4. There are no known workarounds for this vulnerability.

Nextcloud server is an open source home cloud implementation. In affected versions users that should not be able to download a file can still download an older version and use that for uncontrolled distribution. This issue has been addressed in versions 24.0.10 and 25.0.4. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Nextcloud richdocuments is a Nextcloud app integrating the office suit Collabora Online. In affected versions the secure view feature of the rich documents app can be bypassed by using unprotected internal API endpoint of the rich documents app. It is recommended that the Nextcloud Office app (richdocuments) is upgraded to 8.0.0-beta.1, 7.0.2 or 6.3.2. Users unable to upgrade may mitigate the issue by taking steps to restrict the ability to download documents. This includes ensuring that the `WOPI configuration` is configured to only serve documents between Nextcloud and Collabora. It is highly recommended to define the list of Collabora server IPs as the allow list within the Office admin settings of Nextcloud.

Nextcloud server is an open source home cloud implementation. In affected versions the generated fallback password when creating a share was using a weak complexity random number generator, so when the sharer did not change it the password could be guessable to an attacker willing to brute force it. It is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. This issue only affects users who do not have a password policy enabled, so enabling a password policy is an effective mitigation for users unable to upgrade.

Nextcloud server is an open source home cloud implementation. In affected versions admins of a server were able to upload a logo or a favicon and to provided a file name which was not restricted and could overwrite files in the appdata directory. Administrators may have access to overwrite these files by other means but this method could be exploited by tricking an admin into uploading a maliciously named file. It is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. Users unable to upgrade should avoid ingesting logo files from untrusted sources.

Nextcloud iOS is an ios application used to interface with the nextcloud home cloud ecosystem. In versions prior to 4.7.0 when an attacker has physical access to an unlocked device, they may enable the integration into the iOS Files app and bypass the Nextcloud pin/password protection and gain access to a users files. It is recommended that the Nextcloud iOS app is upgraded to 4.7.0. There are no known workarounds for this vulnerability.

Nextcloud android is an android app for interfacing with the nextcloud home server ecosystem. In versions from 3.7.0 and before 3.24.1 an attacker that has access to the unlocked physical device can bypass the Nextcloud Android Pin/passcode protection via a thirdparty app. This allows to see meta information like sharer, sharees and activity of files. It is recommended that the Nextcloud Android app is upgraded to 3.24.1. There are no known workarounds for this vulnerability.

Nextcloud server is an open source home cloud implementation. In releases of the 25.0.x branch before 25.0.3 an inefficient fetch operation may impact server performances and/or can lead to a denial of service. This issue has been addressed and it is recommended that the Nextcloud Server is upgraded to 25.0.3. There are no known workarounds for this vulnerability.

Nextcloud server is an open source home cloud implementation. In affected versions when a recipient receives 2 shares with the same name, while a memory cache is configured, the second share will replace the first one instead of being renamed to `{name} (2)`. It is recommended that the Nextcloud Server is upgraded to 25.0.3 or 24.0.9. Users unable to upgrade should avoid sharing 2 folders with the same name to the same user.

Nextcloud server is an open source home cloud implementation. In affected versions a missing scope validation allowed users to create workflows which are designed to be only available for administrators. Some workflows are designed to be RCE by invoking defined scripts, in order to generate PDFs, invoking webhooks or running scripts on the server. Due to this combination depending on the available apps the issue can result in a RCE at the end. It is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. Users unable to upgrade should disable app `workflow_scripts` and `workflow_pdf_converter` as a mitigation.

Nextcloud server is an open source, personal cloud implementation. In versions from 24.0.0 and before 24.0.9 a user could escalate their permissions to delete files they were not supposed to deletable but only viewed or downloaded. This issue has been addressed andit is recommended that the Nextcloud Server is upgraded to 24.0.9. There are no known workarounds for this vulnerability.

Nextcloud server is an open source, personal cloud implementation. In affected versions a malicious user could try to reset the password of another user and then brute force the 62^21 combinations for the password reset token. As of commit `704eb3aa` password reset attempts are now throttled. Note that 62^21 combinations would significant compute resources to brute force. None the less it is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. There are no known workarounds for this vulnerability.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform, and Nextcloud Enterprise Server is the enterprise version of the file server software. In Nextcloud Server versions 25.0.x prior to 25.0.5 and versions 24.0.x prior to 24.0.10 as well as Nextcloud Enterprise Server versions 25.0.x prior to 25.0.4, 24.0.x prior to 24.0.10, 23.0.x prior to 23.0.12.5, 22.x prior to 22.2.0.10, and 21.x prior to 21.0.9.10, when an attacker gets access to an already logged in user session they can then brute force the password on the confirmation endpoint. Nextcloud Server should upgraded to 24.0.10 or 25.0.4 and Nextcloud Enterprise Server should upgraded to 21.0.9.10, 22.2.10.10, 23.0.12.5, 24.0.10, or 25.0.4 to receive a patch. No known workarounds are available.

Nextcloud is an Open Source private cloud software. Versions 24.0.4 and above, prior to 24.0.7, and 25.0.0 and above, prior to 25.0.1, contain Improper Access Control. Secure view for internal shares can be circumvented if reshare permissions are also given. This issue is patched in versions 24.0.7 and 25.0.1. No workaround is available.

Nextcloud is an Open Source private cloud software. Versions 25.0.0 and above, prior to 25.0.3, are subject to Uncontrolled Resource Consumption. A user can configure a very long password, consuming more resources on password validation than desired. This issue is patched in 25.0.3 No workaround is available.

Nextcloud server is a self hosted home cloud product. In affected versions the `OC\Files\Node\Folder::getFullPath()` function was validating and normalizing the string in the wrong order. The function is used in the `newFile()` and `newFolder()` items, which may allow to creation of paths outside of ones own space and overwriting data from other users with crafted paths. This issue has been addressed in versions 25.0.2, 24.0.8, and 23.0.12. Users are advised to upgrade. There are no known workarounds for this issue.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Nextcloud Server prior to 24.0.8 and 23.0.12 and Nextcloud Enterprise server prior to 24.0.8 and 23.0.12 are vulnerable to server-side request forgery (SSRF). Attackers can leverage enclosed alphanumeric payloads to bypass IP filters and gain SSRF, which would allow an attacker to read crucial metadata if the server is hosted on the AWS platform. Nextcloud Server 24.0.8 and 23.0.2 and Nextcloud Enterprise Server 24.0.8 and 23.0.12 contain a patch for this issue. No known workarounds are available.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Nextcloud Server and Nextcloud Enterprise Server prior to versions 25.0.1 24.0.8, and 23.0.12 missing rate limiting on password reset functionality. This could result in service slowdown, storage overflow, or cost impact when using external email services. Users should upgrade to Nextcloud Server 25.0.1, 24.0.8, or 23.0.12 or Nextcloud Enterprise Server 25.0.1, 24.0.8, or 23.0.12 to receive a patch. No known workarounds are available.

Nextcloud Mail is an email app for the Nextcloud home server platform. Prior to versions 2.2.1, 1.14.5, 1.12.9, and 1.11.8, an attacker can access the mail box by ID getting the subjects and the first characters of the emails. Users should upgrade to Mail 2.2.1 for Nextcloud 25, Mail 1.14.5 for Nextcloud 22-24, Mail 1.12.9 for Nextcloud 21, or Mail 1.11.8 for Nextcloud 20 to receive a patch. No known workarounds are available.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform, and Nextcloud Office is a document collaboration app for the same platform. Nextcloud Server 24.0.x prior to 24.0.8 and 25.0.x prior to 25.0.1, Nextcloud Enterprise Server 24.0.x prior to 24.0.8 and 25.0.x prior to 25.0.1, and Nextcloud Office (Richdocuments) App 6.x prior to 6.3.1 and 7.x prior to 7.0.1 have previews accessible without a watermark. The download should be hidden and the watermark should get applied. This issue is fixed in Nextcloud Server 25.0.1 and 24.0.8, Nextcloud Enterprise Server 25.0.1 and 24.0.8, and Nextcloud Office (Richdocuments) App 7.0.1 (for 25) and 6.3.1 (for 24). No known workarounds are available.

Nextcloud office/richdocuments is an office suit for the nextcloud server platform. In affected versions the Collabora integration can be tricked to provide access to any file without proper permission validation. As a result any user with access to Collabora can obtain the content of other users files. It is recommended that the Nextcloud Office App (Collabora Integration) is updated to 7.0.2 (Nextcloud 25), 6.3.2 (Nextcloud 24), 5.0.10 (Nextcloud 23), 4.2.9 (Nextcloud 21-22), or 3.8.7 (Nextcloud 15-20). There are no known workarounds for this issue.

Nextcloud mail is an email app for the nextcloud home server platform. In affected versions the SMTP, IMAP and Sieve host fields allowed to scan for internal services and servers reachable from within the local network of the Nextcloud Server. It is recommended that the Nextcloud Maill app is upgraded to 1.15.0 or 2.2.2. The only known workaround for this issue is to completely disable the nextcloud mail app.

The Nextcloud Desktop Client is a tool to synchronize files from a Nextcloud Server with your computer. Versions prior to 3.6.3 are missing sanitisation on qml labels which are used for basic HTML elements such as `strong`, `em` and `head` lines in the UI of the desktop client. The lack of sanitisation may allow for javascript injection. It is recommended that the Nextcloud Desktop Client is upgraded to 3.6.3. There are no known workarounds for this issue.

Nextcloud mail is an email app for the nextcloud home server platform. In versions prior to 2.2.2 user's passwords were stored in cleartext in the database during the duration of OAuth2 setup procedure. Any attacker or malicious user with access to the database would have access to these user passwords until the OAuth setup has been completed. It is recommended that the Nextcloud Mail app is upgraded to 2.2.2. There are no known workarounds for this issue.

Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Broken access control allows a user to delete attachments of other users. There are currently no known workarounds. It is recommended that the Nextcloud Deck app is upgraded to 1.6.5 or 1.7.3 or 1.8.2.

Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. A database error can be generated potentially causing a DoS when performed multiple times. There are currently no known workarounds. It is recommended that the Nextcloud Server is upgraded to 1.6.5 or 1.7.3 or 1.8.2.

Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. When getting the reference preview for Deck cards the user has no access to, unauthorized user could eventually get the cached data of a user that has access. There are currently no known workarounds. It is recommended that the Nextcloud app Deck is upgraded to 1.8.2.

Talk-Android enables users to have video & audio calls through Nextcloud on Android. Due to passcode bypass, an attacker is able to access the user's Nextcloud files and view conversations. To exploit this the attacker needs to have physical access to the target's device. There are currently no known workarounds available. It is recommended that the Nextcloud Talk Android app is upgraded to 15.0.2.

Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. It is possible to make a user send any POST request with an arbitrary body given they click on a malicious deep link on a Windows computer. (e.g. in an email, chat link, etc). There are currently no known workarounds. It is recommended that the Nextcloud Desktop client is upgraded to 3.6.2.

Nextcloud Server is an open source personal cloud server. Prior to versions 24.0.7 and 25.0.1, disabled download shares still allow download through preview images. Images could be downloaded and previews of documents (first page) can be downloaded without being watermarked. Versions 24.0.7 and 25.0.1 contain a fix for this issue. No known workarounds are available.

Nextcloud Server is an open source personal cloud server. Prior to versions 23.0.11, 24.0.7, and 25.0.0, there is no password length limit when creating a user as an administrator. An administrator can cause a limited DoS attack against their own server. Versions 23.0.11, 24.0.7, and 25.0.0 contain a fix for the issue. As a workaround, don't create user accounts with long passwords.

Nextcloud Server is an open source personal cloud server. Prior to versions 23.0.10 and 24.0.5, calendar name lengths are not validated before writing to a database. As a result, an attacker can send unnecessary amounts of data against the database. Version 23.0.10 and 24.0.5 contain patches for the issue. No known workarounds are available.

Nexcloud desktop is the Desktop sync client for Nextcloud. An attacker can inject arbitrary HyperText Markup Language into the Desktop Client application. It is recommended that the Nextcloud Desktop client is upgraded to 3.6.1. There are no known workarounds for this issue.

Nexcloud desktop is the Desktop sync client for Nextcloud. An attacker can inject arbitrary HyperText Markup Language into the Desktop Client application via user status and information. It is recommended that the Nextcloud Desktop client is upgraded to 3.6.1. There are no known workarounds for this issue.

Nextcould talk android is the android OS implementation of the nextcloud talk chat system. In affected versions the receiver is not protected by broadcastPermission allowing malicious apps to monitor communication. It is recommended that the Nextcloud Talk Android is upgraded to 14.1.0. There are no known workarounds for this issue.

Nextcloud server is an open source personal cloud server. Affected versions of nextcloud server did not properly limit user display names which could allow a malicious users to overload the backing database and cause a denial of service. It is recommended that the Nextcloud Server is upgraded to 22.2.10, 23.0.7 or 24.0.3. There are no known workarounds for this issue.

Nextcloud also ships a CLI utility called nextcloudcmd which is sometimes used for automated scripting and headless servers. Versions of nextcloudcmd prior to 3.6.1 would incorrectly trust invalid TLS certificates, which may enable a Man-in-the-middle attack that exposes sensitive data or credentials to a network attacker. This affects the CLI only. It does not affect the standard GUI desktop Nextcloud clients, and it does not affect the Nextcloud server.

Nexcloud desktop is the Desktop sync client for Nextcloud. An attacker can inject arbitrary HyperText Markup Language into the Desktop Client application in the notifications. It is recommended that the Nextcloud Desktop client is upgraded to 3.6.1. There are no known workarounds for this issue.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. In version 3.6.0, if a user received a malicious file share and has it synced locally or the virtual filesystem enabled and clicked a nc://open/ link it will open the default editor for the file type of the shared file, which on Windows can also sometimes mean that a file depending on the type, e.g. "vbs", is being executed. It is recommended that the Nextcloud Desktop client is upgraded to version 3.6.1. As a workaround, users can block the Nextcloud Desktop client 3.6.0 by setting the `minimum.supported.desktop.version` system config to `3.6.1` on the server, so new files designed to use this attack vector are not downloaded anymore. Already existing files can still be used. Another workaround would be to enforce shares to be accepted by setting the `sharing.force_share_accept` system config to `true` on the server, so new files designed to use this attack vector are not downloaded anymore. Already existing shares can still be abused.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. In Nextcloud Server prior to versions 23.0.9 and 24.0.5 and Nextcloud Enterprise Server prior to versions 22.2.10.5, 23.0.9, and 24.0.5 an attacker reading `nextcloud.log` may gain knowledge of credentials to connect to a SharePoint service. Nextcloud Server versions 23.0.9 and 24.0.5 and Nextcloud Enterprise Server versions 22.2.10.5, 23.0.9, and 24.0.5 contain a patch for this issue. As a workaround, set `zend.exception_ignore_args = On` as an option in `php.ini`.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Nextcloud Server prior to versions 23.0.10 and 24.0.6 and Nextcloud Enterprise Server prior to versions 22.2.10, 23.0.10, and 24.0.6 are vulnerable to a logged-in attacker slowing down the system by generating a lot of database/cpu load. Nextcloud Server versions 23.0.10 and 24.0.6 and Nextcloud Enterprise Server versions 22.2.10, 23.0.10, and 24.0.6 contain patches for this issue. As a workaround, disable the Circles app.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Nextcloud Server and Nextcloud Enterprise Server prior to versions 23.0.9 and 24.0.5 are vulnerable to exposure of information that cannot be controlled by administrators without direct database access. Versions 23.0.9 and 24.0.5 contains patches for this issue. No known workarounds are available.

Nextcloud Talk is an open source chat, video & audio calls client for the Nextcloud platform. In affected versions an attacker could see the last video frame of any participant who has video disabled but a camera selected. It is recommended that the Nextcloud Talk app is upgraded to 13.0.8 or 14.0.4. Users unable to upgrade should select "None" as camera before joining the call.

Nextcloud android is the official Android client for the Nextcloud home server platform. Internal paths to the Nextcloud Android app files are not properly protected. As a result access to internal files of the from within the Nextcloud Android app is possible. This may lead to a leak of sensitive information in some cases. It is recommended that the Nextcloud Android app is upgraded to 3.21.0. There are no known workarounds for this issue.

Nextcloud server is an open source personal cloud platform. In affected versions it was found that locally running webservices can be found and requested erroneously. It is recommended that the Nextcloud Server is upgraded to 23.0.8 or 24.0.4. It is recommended that the Nextcloud Enterprise Server is upgraded to 22.2.10.4, 23.0.8 or 24.0.4. There are no known workarounds for this issue.

Nextcloud files access control is a nextcloud app to manage access control for files. Users with limited access can see file names in certain cases where they do not have privilege to do so. This issue has been addressed and it is recommended that the Nextcloud Files Access Control app is upgraded to 1.12.2, 1.13.1 or 1.14.1. There are no known workarounds for this issue

Nextcloud server is an open source personal cloud product. Affected versions of this package are vulnerable to Information Exposure which fails to strip the Authorization header on HTTP downgrade. This can lead to account access exposure and compromise. It is recommended that the Nextcloud Server is upgraded to 23.0.7 or 24.0.3. It is recommended that the Nextcloud Enterprise Server is upgraded to 22.2.11, 23.0.7 or 24.0.3. There are no known workarounds for this issue.

Nextcloud Password Policy is an app that enables a Nextcloud server admin to define certain rules for passwords. Prior to versions 22.2.10, 23.0.7, and 24.0.3 the random password generator may, in very rare cases, generate common passwords that the validator itself would block. Upgrade Nextcloud Server to 22.2.10, 23.0.7 or 24.0.3 to receive a patch for the issue in Password Policy. There are no known workarounds available.

Nextcloud Talk is a video and audio conferencing app for Nextcloud. Prior to versions 12.2.7, 13.0.7, and 14.0.3, password protected conversations are susceptible to brute force attacks if the attacker has the link/conversation token. It is recommended that the Nextcloud Talk application is upgraded to 12.2.7, 13.0.7 or 14.0.3. There are currently no known workarounds available apart from not having password protected conversations.

Nextcloud Mail is an email application for the nextcloud personal cloud product. Affected versions of Nextcloud mail would log user passwords to disk in the event of a misconfiguration. Should an attacker gain access to the logs complete access to affected accounts would be obtainable. It is recommended that the Nextcloud Mail is upgraded to 1.12.1. Operators should inspect their logs and remove passwords which have been logged. There are no workarounds to prevent logging in the event of a misconfiguration.

Nextcloud Mail is an email application for the nextcloud personal cloud product. Affected versions shipped with a CSS minifier on the path `./vendor/cerdic/css-tidy/css_optimiser.php`. Access to the minifier is unrestricted and access may lead to Server-Side Request Forgery (SSRF). It is recommendet to upgrade to Mail 1.12.7 or Mail 1.13.6. Users unable to upgrade may manually delete the file located at `./vendor/cerdic/css-tidy/css_optimiser.php`

Nextcloud server is an open source personal cloud solution. The audit log is used to get a full trail of the actions which has been incompletely populated. In affected versions federated share events were not properly logged which would allow brute force attacks to go unnoticed. This behavior exacerbates the impact of CVE-2022-31118. It is recommended that the Nextcloud Server is upgraded to 22.2.7, 23.0.4 or 24.0.0. There are no workarounds available.

Nextcloud server is an open source personal cloud solution. In affected versions an attacker could brute force to find if federated sharing is being used and potentially try to brute force access tokens for federated shares (`a-zA-Z0-9` ^ 15). It is recommended that the Nextcloud Server is upgraded to 22.2.9, 23.0.6 or 24.0.2. Users unable to upgrade may disable federated sharing via the Admin Sharing settings in `index.php/settings/admin/sharing`.

Nextcloud mail is a Mail app for the Nextcloud home server product. Versions of Nextcloud mail prior to 1.12.2 were found to be missing user account ownership checks when performing tasks related to mail attachments. Attachments may have been exposed to incorrect system users. It is recommended that the Nextcloud Mail app is upgraded to 1.12.2. There are no known workarounds for this issue. ### Workarounds No workaround available ### References * [Pull request](https://github.com/nextcloud/mail/pull/6600) * [HackerOne](https://hackerone.com/reports/1579820) ### For more information If you have any questions or comments about this advisory: * Create a post in [nextcloud/security-advisories](https://github.com/nextcloud/security-advisories/discussions) * Customers: Open a support ticket at [support.nextcloud.com](https://support.nextcloud.com)

Nextcloud server is an open source personal cloud server. Affected versions were found to be vulnerable to SMTP command injection. The impact varies based on which commands are supported by the backend SMTP server. However, the main risk here is that the attacker can then hijack an already-authenticated SMTP session and run arbitrary SMTP commands as the email user, such as sending emails to other users, changing the FROM user, and so on. As before, this depends on the configuration of the server itself, but newlines should be sanitized to mitigate such arbitrary SMTP command injection. It is recommended that the Nextcloud Server is upgraded to 22.2.8 , 23.0.5 or 24.0.1. There are no known workarounds for this issue.

richdocuments is the repository for NextCloud Collabra, the app for Nextcloud Office collaboration. Prior to versions 6.0.0, 5.0.4, and 4.2.6, a user could be tricked into working against a remote Office by sending them a federated share. richdocuments versions 6.0.0, 5.0.4 and 4.2.6 contain a fix for this issue. There are currently no known workarounds available.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Prior to versions 22.2.7 and 23.0.4, missing input-size validation of new session names allows users to create app passwords with long names. These long names are then loaded into memory on usage, resulting in impacted performance. Versions 22.2.7 and 23.0.4 contain a fix for this issue. There are currently no known workarounds available.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Prior to versions 22.2.6 and 23.0.3, a user can create a link that is not password protected even if the administrator requires links to be password protected. Versions 22.2.6 and 23.0.3 contain a patch for this issue. There are currently no known workarounds.

Nextcloud Android is the Android client for Nextcloud, a self-hosted productivity platform. Prior to version 3.19.0, sensitive tokens, images, and user related details exist after deletion of a user account. This could result in misuse of the former account holder's information. Nextcloud Android version 3.19.0 contains a patch for this issue. There are no known workarounds available.

Nextcloud Deck is a Kanban-style project & personal management tool for Nextcloud. In versions prior to 1.4.8, 1.5.6, and 1.6.1, an authenticated user can move stacks with cards from their own board to a board of another user. The Nextcloud Deck app contains a patch for this issue in versions 1.4.8, 1.5.6, and 1.6.1. There are no known currently-known workarounds available.

Nextcloud Deck is a Kanban-style project & personal management tool for Nextcloud, similar to Trello. The full path of the application is exposed to unauthorized users. It is recommended that the Nextcloud Deck app is upgraded to 1.2.11, 1.4.6, or 1.5.4. There is no workaround available.

Nextcloud Talk is a video and audio conferencing app for Nextcloud. In versions prior to 13.0.5 and 14.0.0, a call moderator can indirectly enable user webcams by granting permissions, if they were enabled before removing the permissions. A patch is available in versions 13.0.5 and 14.0.0. There are currently no known workarounds.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Prior to versions 21.0.8, 22.2.4, and 23.0.1, it is possible to trick administrators into enabling "recommended" apps for the Nextcloud server that they do not need, thus expanding their attack surface unnecessarily. This issue is fixed in versions 21.0.8 , 22.2.4, and 23.0.1.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. Prior to versions 20.0.14.4, 21.0.8, 22.2.4, and 23.0.1, it is possible to create files and folders that have leading and trailing \n, \r, \t, and \v characters. The server rejects files and folders that have these characters in the middle of their names, so this might be an opportunity for injection. This issue is fixed in versions 20.0.14.4, 21.0.8, 22.2.4, and 23.0.1. There are currently no known workarounds.

Nextcloud Talk is a video and audio conferencing app for Nextcloud, a self-hosted productivity platform. Prior to versions 11.3.4, 12.2.2, and 13.0.0, when sharing a Deck card in conversation, the metaData can be manipulated so users can be tricked into opening arbitrary URLs. This issue is fixed in versions 11.3.4, 12.2.2, and 13.0.0. There are currently no known workarounds.

Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. In versions prior to 3.19.0, any application with notification permission can access contacts if Nextcloud has access to Contacts without applying for the Contacts permission itself. Version 3.19.0 contains a fix for this issue. There are currently no known workarounds.

Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. Prior to version 3.19.1, users can bypass a lock on the Nextcloud app on an Android device by repeatedly reopening the app. Version 3.19.1 contains a fix for the problem. There are currently no known workarounds.

Nextcloud Calendar is a calendar application for the nextcloud framework. SMTP Command Injection in Appointment Emails via Newlines: as newlines and special characters are not sanitized in the email value in the JSON request, a malicious attacker can inject newlines to break out of the `RCPT TO:<BOOKING USER'S EMAIL> ` SMTP command and begin injecting arbitrary SMTP commands. It is recommended that Calendar is upgraded to 3.2.2. There are no workaround available.

Nextcloud text is a collaborative document editing using Markdown built for the nextcloud server. Due to an issue with the Nextcloud Text application, which is by default shipped with Nextcloud Server, an attacker is able to access the folder names of "File Drop". For successful exploitation an attacker requires knowledge of the sharing link. It is recommended that users upgrade their Nextcloud Server to 20.0.14, 21.0.6 or 22.2.1. Users unable to upgrade should disable the Nextcloud Text application in the application settings.

Nextcloud server is an open source, self hosted cloud style services platform. In affected versions an attacker can cause a denial of service by uploading specially crafted files which will cause the server to allocate too much memory / CPU. It is recommended that the Nextcloud Server is upgraded to 21.0.8 , 22.2.4 or 23.0.1. Users unable to upgrade should disable preview generation with the `'enable_previews'` config flag.

Nextcloud server is a self hosted system designed to provide cloud style services. The groupfolders application for Nextcloud allows sharing a folder with a group of people. In addition, it allows setting "advanced permissions" on subfolders, for example, a user could be granted access to the groupfolder but not specific subfolders. Due to a lacking permission check in affected versions, a user could still access these subfolders by copying the groupfolder to another location. It is recommended that the Nextcloud Server is upgraded to 20.0.14, 21.0.6 or 22.2.1. Users unable to upgrade should disable the "groupfolders" application in the admin settings.

Nextcloud server is a self hosted system designed to provide cloud style services. In affected versions the User Status API did not consider the user enumeration settings by the administrator. This allowed a user to enumerate other users on the instance, even when user listings where disabled. It is recommended that the Nextcloud Server is upgraded to 20.0.14, 21.0.6 or 22.2.1. There are no known workarounds.

Nextcloud talk is a self hosting messaging service. In versions prior to 12.3.0 the Nextcloud Android Talk application did not properly detect the lockscreen state when a call was incoming. If an attacker got physical access to the locked phone, and the victim received a phone call the attacker could gain access to the chat messages and files of the user. It is recommended that the Nextcloud Android Talk App is upgraded to 12.3.0. There are no known workarounds.

Nextcloud talk is a self hosting messaging service. In versions prior 12.1.2 an attacker is able to control the link of a geolocation preview in the Nextcloud Talk application due to a lack of validation on the link. This could result in an open-redirect, but required user interaction. This only affected users of the Android Talk client. It is recommended that the Nextcloud Talk App is upgraded to 12.1.2. There are no known workarounds.

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. An issue in versions prior to 3.17.1 may lead to sensitive information disclosure. An unauthorized app that does not have the otherwise required `MANAGE_DOCUMENTS` permission may view image thumbnails for images it does not have permission to view. Version 3.17.1 contains a patch. There are no known workarounds.

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. The Nextcloud Android app uses content providers to manage its data. Prior to version 3.18.1, the providers `FileContentProvider` and `DiskLruImageCacheFileProvider` have security issues (an SQL injection, and an insufficient permission control, respectively) that allow malicious apps in the same device to access Nextcloud's data bypassing the permission control system. Users should upgrade to version 3.18.1 to receive a patch. There are no known workarounds aside from upgrading.

nextcloud news-android is an Android client for the Nextcloud news/feed reader app. In affected versions the Nextcloud News for Android app has a security issue by which a malicious application installed on the same device can send it an arbitrary Intent that gets reflected back, unintentionally giving read and write access to non-exported Content Providers in Nextcloud News for Android. Users should upgrade to version 0.9.9.63 or higher as soon as possible.

Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud Talk application was vulnerable to a stored Cross-Site Scripting (XSS) vulnerability. For exploitation, a user would need to right-click on a malicious file and open the file in a new tab. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. It is recommended that the Nextcloud Talk application is upgraded to patched versions 10.0.7, 10.1.4, 11.1.2, 11.2.0 or 12.0.0. As a workaround, use a browser that has support for Content-Security-Policy.

Nextcloud is an open-source, self-hosted productivity platform. Prior to versions 20.0.13, 21.0.5, and 22.2.0, Nextcloud Server did not implement a database backend for rate-limiting purposes. Any component of Nextcloud using rate-limits (as as `AnonRateThrottle` or `UserRateThrottle`) was thus not rate limited on instances not having a memory cache backend configured. In the case of a default installation, this would notably include the rate-limits on the two factor codes. It is recommended that the Nextcloud Server be upgraded to 20.0.13, 21.0.5, or 22.2.0. As a workaround, enable a memory cache backend in `config.php`.

Nextcloud is an open-source, self-hosted productivity platform. A missing permission check in Nextcloud Deck before 1.2.9, 1.4.5 and 1.5.3 allows another authenticated users to access Deck cards of another user. It is recommended that the Nextcloud Deck App is upgraded to 1.2.9, 1.4.5 or 1.5.3. There are no known workarounds aside from upgrading.

Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud OfficeOnline application prior to version 1.1.1 returned verbatim exception messages to the user. This could result in a full path disclosure on shared files. (e.g. an attacker could see that the file `shared.txt` is located within `/files/$username/Myfolder/Mysubfolder/shared.txt`). It is recommended that the OfficeOnline application is upgraded to 1.1.1. As a workaround, one may disable the OfficeOnline application in the app settings.

Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud Richdocuments application prior to versions 3.8.6 and 4.2.3 returned verbatim exception messages to the user. This could result in a full path disclosure on shared files. (e.g. an attacker could see that the file `shared.txt` is located within `/files/$username/Myfolder/Mysubfolder/shared.txt`). It is recommended that the Richdocuments application is upgraded to 3.8.6 or 4.2.3. As a workaround, disable the Richdocuments application in the app settings.

Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud Contacts application prior to version 4.0.3 was vulnerable to a stored Cross-Site Scripting (XSS) vulnerability. For exploitation, a user would need to right-click on a malicious file and open the file in a new tab. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. It is recommended that the Nextcloud Contacts application is upgraded to 4.0.3. As a workaround, one may use a browser that has support for Content-Security-Policy.

Nextcloud is an open-source, self-hosted productivity platform The Nextcloud Mail application prior to versions 1.10.4 and 1.11.0 does by default not render images in emails to not leak the read state or user IP. The privacy filter failed to filter images with a relative protocol. It is recommended that the Nextcloud Mail application is upgraded to 1.10.4 or 1.11.0. There are no known workarounds aside from upgrading.

Nextcloud server is an open source, self hosted personal cloud. Nextcloud supports rendering image previews for user provided file content. For some image types, the Nextcloud server was invoking a third-party library that wasn't suited for untrusted user-supplied content. There are several security concerns with passing user-generated content to this library, such as Server-Side-Request-Forgery, file disclosure or potentially executing code on the system. The risk depends on your system configuration and the installed library version. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. These versions do not use this library anymore. As a workaround users may disable previews by setting `enable_previews` to `false` in `config.php`.

Nextcloud server is an open source, self hosted personal cloud. In affected versions logging of exceptions may have resulted in logging potentially sensitive key material for the Nextcloud Encryption-at-Rest functionality. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. If upgrading is not an option users are advised to disable system logging to resolve this issue until such time that an upgrade can be performed Note that ff you do not use the Encryption-at-Rest functionality of Nextcloud you are not affected by this bug.

Nextcloud server is an open source, self hosted personal cloud. In affected versions an attacker is able to bypass Two Factor Authentication in Nextcloud. Thus knowledge of a password, or access to a WebAuthN trusted device of a user was sufficient to gain access to an account. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. There are no workaround for this vulnerability.

Nextcloud Richdocuments is an open source collaborative office suite. In affected versions there is a lack of rate limiting on the Richdocuments OCS endpoint. This may have allowed an attacker to enumerate potentially valid share tokens. It is recommended that the Nextcloud Richdocuments app is upgraded to either 3.8.4 or 4.2.1 to resolve. For users unable to upgrade it is recommended that the Richdocuments application be disabled.

Nextcloud Richdocuments is an open source collaborative office suite. In affected versions the File Drop features ("Upload Only" public link shares in Nextcloud) can be bypassed using the Nextcloud Richdocuments app. An attacker was able to read arbitrary files in such a share. It is recommended that the Nextcloud Richdocuments is upgraded to 3.8.4 or 4.2.1. If upgrading is not possible then it is recommended to disable the Richdocuments application.

Nextcloud Text is an open source plaintext editing application which ships with the nextcloud server. In affected versions the Nextcloud Text application returned different error messages depending on whether a folder existed in a public link share. This is problematic in case the public link share has been created with "Upload Only" privileges. (aka "File Drop"). A link share recipient is not expected to see which folders or files exist in a "File Drop" share. Using this vulnerability an attacker is able to enumerate folders in such a share. Exploitation requires that the attacker has access to a valid affected "File Drop" link share. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.0.1. Users who are unable to upgrade are advised to disable the Nextcloud Text application in the app settings.

Deck is an open source kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. In affected versions the Deck application didn't properly check membership of users in a Circle. This allowed other users in the instance to gain access to boards that have been shared with a Circle, even if the user was not a member of the circle. It is recommended that Nextcloud Deck is upgraded to 1.5.1, 1.4.4 or 1.2.9. If you are unable to update it is advised to disable the Deck plugin.

Nextcloud Circles is an open source social network built for the nextcloud ecosystem. In affected versions the Nextcloud Circles application allowed any user to join any "Secret Circle" without approval by the Circle owner leaking private information. It is recommended that Nextcloud Circles is upgraded to 0.19.15, 0.20.11 or 0.21.4. There are no workarounds for this issue.

Nextcloud Circles is an open source social network built for the nextcloud ecosystem. In affected versions the Nextcloud Circles application is vulnerable to a stored Cross-Site Scripting (XSS) vulnerability. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. It is recommended that the Nextcloud Circles application is upgraded to 0.21.3, 0.20.10 or 0.19.14 to resolve this issue. As a workaround users may use a browser that has support for Content-Security-Policy. A notable exemption is Internet Explorer which does not support CSP properly.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. The Nextcloud Desktop Client invokes its uninstaller script when being installed to make sure there are no remnants of previous installations. In versions 3.0.3 through 3.2.4, the Client searches the `Uninstall.exe` file in a folder that can be written by regular users. This could lead to a case where a malicious user creates a malicious `Uninstall.exe`, which would be executed with administrative privileges on the Nextcloud Desktop Client installation. This issue is fixed in Nextcloud Desktop Client version 3.3.0. As a workaround, do not allow untrusted users to create content in the `C:\` system folder and verify that there is no malicious `C:\Uninstall.exe` file on the system.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.

Nextcloud Richdocuments in an open source self hosted online office. Nextcloud uses the WOPI ("Web Application Open Platform Interface") protocol to communicate with the Collabora Editor, the communication between these two services was not protected by a credentials or IP check. Whilst this does not result in gaining access to data that the user has not yet access to, it can result in a bypass of any enforced watermark on documents as described on the [Nextcloud Virtual Data Room](https://nextcloud.com/virtual-data-room/) website and [our documentation](https://portal.nextcloud.com/article/nextcloud-and-virtual-data-room-configuration-59.html). The Nextcloud Richdocuments releases 3.8.3 and 4.2.0 add an additional admin settings for an allowlist of IP addresses that can access the WOPI API. We recommend upgrading and configuring the allowlist to a list of Collabora servers. There is no known workaround. Note that this primarily results a bypass of any configured watermark or download protection using File Access Control. If you do not require or rely on these as a security feature no immediate action is required on your end.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, there was a lack of ratelimiting on the public share link mount endpoint. This may have allowed an attacker to enumerate potentially valid share tokens. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, the Nextcloud Text application shipped with Nextcloud Server returned verbatim exception messages to the user. This could result in a full path disclosure on shared files. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. As a workaround, one may disable the Nextcloud Text application in Nextcloud Server app settings.

Nextcloud Text is a collaborative document editing application that uses Markdown. A cross-site scripting vulnerability is present in versions prior to 19.0.13, 20.0.11, and 21.0.3. The Nextcloud Text application shipped with Nextcloud server used a `text/html` Content-Type when serving files to users. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. As a workaround, use a browser that has support for Content-Security-Policy.

Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, webauthn tokens were not deleted after a user has been deleted. If a victim reused an earlier used username, the previous user could gain access to their account. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, default share permissions were not being respected for federated reshares of files and folders. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds.

Nextcloud Mail is a mail app for Nextcloud. In versions prior to 1.9.6, the Nextcloud Mail application does not, by default, render images in emails to not leak the read state. The privacy filter failed to filter images with a `background-image` CSS attribute. Note that the images were still passed through the Nextcloud image proxy, and thus there was no IP leakage. The issue was patched in version 1.9.6 and 1.10.0. No workarounds are known to exist.

Nextcloud Talk is a fully on-premises audio/video and chat communication service. In versions prior to 11.2.2, if a user was able to reuse an earlier used username, they could get access to any chat message sent to the previous user with this username. The issue was patched in versions 11.2.2 and 11.3.0. As a workaround, don't allow users to choose usernames themselves. This is the default behaviour of Nextcloud, but some user providers may allow doing so.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, there was a lack of ratelimiting on the public DAV endpoint. This may have allowed an attacker to enumerate potentially valid share tokens or credentials. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, there was a lack of ratelimiting on the shareinfo endpoint. This may have allowed an attacker to enumerate potentially valid share tokens. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds.

Nextcloud Server is a Nextcloud package that handles data storage. Nextcloud Server supports application specific tokens for authentication purposes. These tokens are supposed to be granted to a specific applications (e.g. DAV sync clients), and can also be configured by the user to not have any filesystem access. Due to a lacking permission check, the tokens were able to change their own permissions in versions prior to 19.0.13, 20.0.11, and 21.0.3. Thus fileystem limited tokens were able to grant themselves access to the filesystem. The issue is patched in versions 19.0.13, 20.0.11, and 21.0.3. There are no known workarounds aside from upgrading.

Nextcloud Server is a Nextcloud package that handles data storage. In versions priot to 19.0.13, 20.0.11, and 21.0.3, Nextcloud Server audit logging functionality wasn't properly logging events for the unsetting of a share expiration date. This event is supposed to be logged. This issue is patched in versions 19.0.13, 20.0.11, and 21.0.3.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.0.11, and 21.0.3, filenames where not escaped by default in controllers using `DownloadResponse`. When a user-supplied filename was passed unsanitized into a `DownloadResponse`, this could be used to trick users into downloading malicious files with a benign file extension. This would show in UI behaviours where Nextcloud applications would display a benign file extension (e.g. JPEG), but the file will actually be downloaded with an executable file extension. The vulnerability is patched in versions 19.0.13, 20.0.11, and 21.0.3. Administrators of Nextcloud instances do not have a workaround available, but developers of Nextcloud apps may manually escape the file name before passing it into `DownloadResponse`.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.0.11, and 21.0.3, ratelimits are not applied to OCS API responses. This affects any OCS API controller (`OCSController`) using the `@BruteForceProtection` annotation. Risk depends on the installed applications on the Nextcloud Server, but could range from bypassing authentication ratelimits or spamming other Nextcloud users. The vulnerability is patched in versions 19.0.13, 20.0.11, and 21.0.3. No workarounds aside from upgrading are known to exist.

Nextcloud Android app is the Android client for Nextcloud. In versions prior to 3.15.1, a malicious application on the same device is possible to crash the Nextcloud Android Client due to an uncaught exception. The vulnerability is patched in version 3.15.1.

Nextcloud Android app is the Android client for Nextcloud. In versions prior to 3.16.1, a malicious app on the same device could have gotten access to the shared preferences of the Nextcloud Android application. This required user-interaction as a victim had to initiate the sharing flow and choose the malicious app. The shared preferences contain some limited private data such as push tokens and the account name. The vulnerability is patched in version 3.16.1.

Nextcloud Talk is a fully on-premises audio/video and chat communication service. Password protected shared chats in Talk before version 9.0.10, 10.0.8 and 11.2.2 did not rotate the session cookie after a successful authentication event. It is recommended that the Nextcloud Talk App is upgraded to 9.0.10, 10.0.8 or 11.2.2. No workarounds for this vulnerability are known to exist.

Nextcloud server before 19.0.11, 20.0.10, 21.0.2 is vulnerable to brute force attacks due to lack of inclusion of IPv6 subnets in rate-limiting considerations. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.

Nextcloud Deck before 1.2.7, 1.4.1 suffers from an information disclosure vulnerability when searches for sharees utilize the lookup server by default instead of only the local Nextcloud server unless a global search has been explicitly chosen by the user.

Nextcloud iOS before 3.4.2 suffers from an information disclosure vulnerability when searches for sharees utilize the lookup server by default instead of only on the local Nextcloud server unless a global search has been explicitly chosen by the user.

Nextcloud End-to-End Encryption before 1.5.3, 1.6.3 and 1.7.1 suffers from a denial of service vulnerability due to permitting any authenticated users to lock files of other users.

Nextcloud Android App (com.nextcloud.client) before v3.16.0 is vulnerable to information disclosure due to searches for sharees being performed by default on the lookup server instead of only using the local Nextcloud server unless a global search has been explicitly chosen by the user.

Nextcloud Mail before 1.9.5 suffers from improper access control due to a missing permission check allowing other authenticated users to create mail aliases for other users.

Nextcloud Desktop Client before 3.3.1 is vulnerable to improper certificate validation due to lack of SSL certificate verification when using the "Register with a Provider" flow.

Nextcloud Android is the Android client for the Nextcloud open source home cloud system. Due to a timeout issue the Android client may not properly clean all sensitive data on account removal. This could include sensitive key material such as the End-to-End encryption keys. It is recommended that the Nextcloud Android App is upgraded to 3.16.1

Nextcloud Server is a Nextcloud package that handles data storage. In versions of Nextcloud Server prior to 10.0.11, 20.0.10, and 21.0.2, a malicious user may be able to break the user administration page. This would disallow administrators to administrate users on the Nextcloud instance. The vulnerability is fixed in versions 19.0.11, 20.0.10, and 21.0.2. As a workaround, administrators can use the OCC command line tool to administrate the Nextcloud users.

Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the "Add server automatically once a federated share was created successfully" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable "Add server automatically once a federated share was created successfully" in the Nextcloud settings.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.11, 20.0.10, and 21.0.2, an attacker is able to convert a Files Drop link to a federated share. This causes an issue on the UI side of the sharing user. When the sharing user opens the sharing panel and tries to remove the "Create" privileges of this unexpected share, Nextcloud server would silently grant the share read privileges. The vulnerability is patched in versions 19.0.11, 20.0.10 and 21.0.2. No workarounds are known to exist.

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.11, 20.0.10, and 21.0.2, an attacker is able to receive write/read privileges on any Federated File Share. Since public links can be added as federated file share, this can also be exploited on any public link. Users can upgrade to patched versions (19.0.11, 20.0.10 or 21.0.2) or, as a workaround, disable federated file sharing.

Nextcloud Server is a Nextcloud package that handles data storage. Nextcloud Server versions prior to 19.0.11, 20.0.10, or 21.0.2 send user IDs to the lookup server even if the user has no fields set to published. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2; no workarounds outside the updates are known to exist.

Nextcloud Mail is a mail app for the Nextcloud platform. A missing permission check in Nextcloud Mail before 1.4.3 and 1.8.2 allows another authenticated users to access mail metadata of other users. Versions 1.4.3 and 1.8.2 contain patches for this vulnerability; no workarounds other than the patches are known to exist.

Nextcloud Desktop Client prior to 3.1.3 is vulnerable to resource injection by way of missing validation of URLs, allowing a malicious server to execute remote commands. User interaction is needed for exploitation.

Nextcloud Server prior to 20.0.6 is vulnerable to reflected cross-site scripting (XSS) due to lack of sanitization in `OC.Notification.show`.

A missing user check in Nextcloud prior to 20.0.6 inadvertently populates a user's own credentials for other users external storage configuration when not already configured yet.

Nextcloud Server prior to 20.0.0 stores passwords in a recoverable format even when external storage is not configured.

Nextcloud Deck before 1.0.2 suffers from an insecure direct object reference (IDOR) vulnerability that permits users with a duplicate user identifier to access deck data of a previous deleted user.

A missing link validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows execution of a stored XSS attack using Internet Explorer when saving a 'javascript:' URL in markdown format.

A wrong check in Nextcloud Server 19 and prior allowed to perform a denial of service attack when resetting the password for a user.

A missing input validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows users to store unlimited data in workflow rules causing load and potential DDoS on later interactions and usage with those rules.

A missing file type check in Nextcloud Contacts 3.3.0 allows a malicious user to upload malicious SVG files to perform cross-site scripting (XSS) attacks.

A missing file type check in Nextcloud Contacts 3.4.0 allows a malicious user to upload SVG files as PNG files to perform cross-site scripting (XSS) attacks.

Missing validation of server certificates for out-going connections in Nextcloud Social < 0.4.0 allowed a man-in-the-middle attack.

Improper access control in Nextcloud Social app version 0.3.1 allowed to read posts of any user.

Insufficient protection of the server-side encryption keys in Nextcloud Server 19.0.1 allowed an attacker to replace the encryption keys.

Insufficient protection of the server-side encryption keys in Nextcloud Server 19.0.1 allowed an attacker to replace the public key to decrypt them later on.

A cryptographic issue in Nextcloud Server 19.0.1 allowed an attacker to downgrade the encryption scheme and break the integrity of encrypted files.

A wrong generation of the passphrase for the encrypted block in Nextcloud Server 19.0.1 allowed an attacker to overwrite blocks in a file.

A wrong configuration in Nextcloud Server 19.0.1 incorrectly made the user feel the passwordless WebAuthn is also a two factor verification by asking for the PIN of the passwordless WebAuthn but not verifying it.

A logic error in Nextcloud Server 19.0.0 caused a plaintext storage of the share password when it was given on the initial create API call.

A too small set of random characters being used for encryption in Nextcloud Server 18.0.4 allowed decryption in shorter time than intended.

Missing access control in Nextcloud Deck 1.0.4 caused an insecure direct object reference allowing an attacker to view all attachments.

A missing rate limit in the Preferred Providers app 1.7.0 allowed an attacker to set the password an uncontrolled amount of times.

A logic error in Nextcloud Server 19.0.0 caused a privilege escalation allowing malicious users to reshare with higher permissions than they got assigned themselves.

Improper access control in Nextcloud Deck 0.8.0 allowed an attacker to reshare boards shared with them with more permissions than they had themselves.

A cleartext storage of sensitive information in Nextcloud Desktop Client 2.6.4 gave away information about used proxies and their authentication credentials.

Missing sanitization of a server response in Nextcloud Desktop Client 2.6.4 for Linux allowed a malicious Nextcloud Server to store files outside of the dedicated sync directory.

A cross-site scripting error in Nextcloud Desktop client 2.6.4 allowed to present any html (including local links) when responding with invalid data on the login attempt.

A memory corruption vulnerability exists in NextCloud Desktop Client v2.6.4 where missing ASLR and DEP protections in for windows allowed to corrupt memory.

A memory leak in the OCUtil.dll library used by Nextcloud Desktop Client 2.6.4 can lead to a DoS against the host system.

A code injection in Nextcloud Desktop Client 2.6.4 allowed to load arbitrary code when placing a malicious OpenSSL config into a fixed directory.

Improper check of inputs in Nextcloud Preferred Providers app v1.6.0 allowed to perform a denial of service attack when using a very long password.

A missing file type check in Nextcloud Contacts 3.2.0 allowed a malicious user to upload any file as avatars.

Improper access control in Nextcloud Deck 1.0.0 allowed an attacker to inject tasks into other users decks.

A too lax check in Nextcloud Talk 6.0.4, 7.0.2 and 8.0.7 allowed a code injection when a not correctly sanitized talk command was added by an administrator.

A missing verification of the TLS host in Nextcloud Mail 1.1.3 allowed a man in the middle attack.

An outdated 3rd party library in the Files PDF viewer for Nextcloud Server 18.0.2 caused a Cross-site scripting vulnerability when opening a malicious PDF.

An Insecure direct object reference vulnerability in Nextcloud Server 18.0.2 allowed an attacker to remote wipe devices of other users when sending a malicious request directly to the endpoint.

Improper access control in Groupfolders app 4.0.3 allowed to delete hidden directories when when renaming an accessible item to the same name.

A code injection in Nextcloud Desktop Client 2.6.2 for macOS allowed to load arbitrary code when starting the client with DYLD_INSERT_LIBRARIES set in the environment.

A missing access control check in Nextcloud Server < 18.0.1, < 17.0.4, and < 16.0.9 causes hide-download shares to be downloadable when appending /download to the URL.

A missing check for IPv4 nested inside IPv6 in Nextcloud server < 17.0.1, < 16.0.7, and < 15.0.14 allowed a Server-Side Request Forgery (SSRF) vulnerability when subscribing to a malicious calendar URL.

A missing check in Nextcloud Server 14.0.3 could give recipient the possibility to extend the expiration date of a share they received.

A bug in Nextcloud Server 14.0.4 could expose more data in reshared link shares than intended by the sharer.

A reflected Cross-Site Scripting vulnerability in Nextcloud Server 16.0.1 was discovered in the svg generation.

Improper authorization in Nextcloud server 17.0.0 causes leaking of previews and files when a file-drop share link is opened via the gallery app.

An authenticated server-side request forgery in Nextcloud server 16.0.1 allowed to detect local and remote services when adding a new subscription in the calendar application.

Improper preservation of permissions in Nextcloud Server 14.0.3 causes the event details to be leaked when sharing a non-public event.

Improper Input Validation in Nextcloud Server 15.0.7 allows group admins to create users with IDs of system folders.

Exposure of Private Information in Nextcloud Server 16.0.1 causes the server to send it's domain and user IDs to the Nextcloud Lookup Server without any further data when the Lookup server is disabled.

Not strictly enough sanitization in the Nextcloud Android app 3.6.0 allowed an attacker to get content information from protected tables when using custom queries.

Improper permissions preservation in Nextcloud Server 16.0.1 causes sharees to be able to reshare with write permissions when sharing the mount point of a share they received, as a public link.

Improper access control in Nextcloud Talk 6.0.3 leaks the existance and the name of private conversations when linked them to another shared item via the projects feature.

Improper neutralization of file names, conversation names and board names in Nextcloud Server 16.0.3, Nextcloud Talk 6.0.3 and Nextcloud Deck 0.6.5 causes an XSS when linking them with each others in a project.

Missing escaping of HTML in the Updater of Nextcloud 15.0.5 allowed a reflected XSS when starting the updater from a malicious location.

A missing check in Nextcloud Server 17.0.0 allowed an attacker to set up a new second factor when trying to login.

Dangling remote share attempts in Nextcloud 16 allow a DNS pollution when running long.

A wrong check for the system time in the Android App 3.9.0 causes a bypass of the lock protection when changing the time of the system to the past.

Missing sanitization in the iOS App 2.24.4 causes an XSS when opening malicious HTML files.

A bug in Nextcloud Server 17.0.1 causes the workflow rules to depend their behaviour on the file extension when checking file mimetypes.

A bug in Nextcloud Server 15.0.2 causes pending 2FA logins to not be correctly expired when the password of the user is reset.

Violation of Secure Design Principles in the iOS App 2.23.0 causes the app to leak its login and token to other Nextcloud services when search e.g. for federated users or registering for push notifications.

Improper authorization in the Circles app 0.17.7 causes retaining access when an email address was removed from a circle.

An SQL Injection in the Nextcloud Lookup-Server < v0.3.0 (running on https://lookup.nextcloud.com) caused unauthenticated users to be able to execute arbitrary SQL commands.

Bypassing lock protection exists in Nextcloud Android app 3.6.0 when creating a multi-account and aborting the process.

SQL Injection in the Nextcloud Android app prior to version 3.0.0 allows to destroy a local cache when a harmful query is executed requiring to resetup the account.

Bypass lock protection in the Nextcloud Android app prior to version 3.3.0 allowed access to files when being prompted for the lock protection and switching to the Nextcloud file provider.

Bypass lock protection in the Nextcloud Android app prior to version 3.6.2 causes leaking of thumbnails when requesting the Android content provider although the lock protection was not solved.

Bypass lock protection in the Nextcloud Android app prior to version 3.6.1 allows accessing the files when repeatedly opening and closing the app in a very short time.

Improper sanitization of HTML in directory names in the Nextcloud Android app prior to version 3.7.0 allowed to style the directory name in the header bar when using basic HTML.

A missing check in the Nextcloud Server prior to version 15.0.1 causes leaking of calendar event names when adding or modifying confidential or private events.

lib/Controller/ExtractionController.php in the Extract add-on before 1.2.0 for Nextcloud allows Remote Code Execution via shell metacharacters in a RAR filename via ajax/extractRar.php (nameOfFile and directory parameters).

A missing check in Nextcloud Server prior to 14.0.0 could give unauthorized access to the previews of single file password protected shares.

Improper revalidation of permissions in Nextcloud Server prior to 14.0.0, 13.0.6 and 12.0.11 lead to not accepting access restrictions by acess tokens.

Missing state in Nextcloud Server prior to 14.0.0 would not enforce the use of a second factor at login if the the provider of the second factor failed to load.

A missing access check in Nextcloud Server prior to 14.0.0 could lead to continued access to password protected link shares when the owner had changed the password.

A bug causing session fixation in Nextcloud Server prior to 14.0.0, 13.0.3 and 12.0.8 could potentially allow an attacker to obtain access to password protected shares.

A missing sanitization of search results for an autocomplete field in NextCloud Talk <3.2.5 could lead to a stored XSS requiring user-interaction. The missing sanitization only affected user names, hence malicious search results could only be crafted by authenticated users.

A missing sanitization of search results for an autocomplete field in NextCloud Server <13.0.5 could lead to a stored XSS requiring user-interaction. The missing sanitization only affected user names, hence malicious search results could only be crafted by authenticated users.

Improper input validator in Nextcloud Server prior to 12.0.3 and 11.0.5 could lead to an attacker's actions not being logged in the audit log.

Improper Authentication in Nextcloud Server prior to version 12.0.3 would allow an attacker that obtained user credentials to bypass the 2 Factor Authentication.

In Nextcloud Contacts before 2.1.2, a missing sanitization of search results for an autocomplete field could lead to a stored XSS requiring user-interaction. The missing sanitization only affected group names, hence malicious search results could only be crafted by privileged users like admins or group admins.

In Nextcloud Calendar before 1.5.8 and 1.6.1, a missing sanitization of search results for an autocomplete field could lead to a stored XSS requiring user-interaction. The missing sanitization only affected group names, hence malicious search results could only be crafted by privileged users like admins or group admins.

Nextcloud Server before 12.0.8 and 13.0.3 suffers from improper checks of dropped permissions for incoming shares allowing a user to still request previews for files it should not have access to.

Nextcloud Server before 12.0.8 and 13.0.3 suffer from improper authentication on the OAuth2 token endpoint. Missing checks potentially allowed handing out new tokens in case the OAuth2 client was partly compromised.

Nextcloud Server before 11.0.7 and 12.0.5 suffers from an Authorization Bypass Through User-Controlled Key vulnerability. A missing ownership check allowed logged-in users to change the scope of app passwords of other users. Note that the app passwords themselves where neither disclosed nor could the error be misused to identify as another user.

Nextcloud Server before 10.0.4 and 11.0.2 are vulnerable to disclosure of calendar and addressbook names to other logged-in users. Note that no actual content of the calendar and addressbook has been disclosed.

Nextcloud Server before 11.0.3 is vulnerable to disclosure of valid share tokens for public calendars due to a logical error. Thus granting an attacker potentially access to publicly shared calendars without knowing the share token.

Nextcloud Server before 9.0.58 and 10.0.5 and 11.0.3 are shipping a vulnerable JavaScript library for sanitizing untrusted user-input which suffered from a XSS vulnerability caused by a behaviour change in Safari 10.1 and 10.2. Note that Nextcloud employs a strict Content-Security-Policy preventing exploitation of this XSS issue on modern web browsers.

Nextcloud Server before 11.0.3 is vulnerable to an improper session handling allowed an application specific password without permission to the files access to the users file.

Nextcloud Server before 9.0.58 and 10.0.5 and 11.0.3 are vulnerable to an inadequate escaping of error messages leading to XSS vulnerabilities in multiple components.

Nextcloud Server before 11.0.3 is vulnerable to an inadequate escaping leading to a XSS vulnerability in the search module. To be exploitable a user has to write or paste malicious content into the search dialogue.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a Content-Spoofing vulnerability in the "files" app. The top navigation bar displayed in the files list contained partially user-controllable input leading to a potential misrepresentation of information.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a bypass in the quota limitation. Due to not properly sanitizing values provided by the `OC-Total-Length` HTTP header an authenticated adversary may be able to exceed their configured user quota. Thus using more space than allowed by the administrator.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a Denial of Service attack. Due to an error in the application logic an authenticated adversary may trigger an endless recursion in the application leading to a potential Denial of Service.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a error message disclosing existence of file in write-only share. Due to an error in the application logic an adversary with access to a write-only share may enumerate the names of existing files and subfolders by comparing the exception messages.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a creation of folders in read-only folders despite lacking permissions issue. Due to a logical error in the file caching layer an authenticated adversary is able to create empty folders inside a shared folder. Note that this only affects folders and files that the adversary has at least read-only permissions for.

Nextcloud Server before 9.0.55 and 10.0.2 suffers from a permission increase on re-sharing via OCS API issue. A permission related issue within the OCS sharing API allowed an authenticated adversary to reshare shared files with an increasing permission set. This may allow an attacker to edit files in a share despite having only a 'read' permission set. Note that this only affects folders and files that the adversary has at least read-only permissions for.

Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.0.6 and 9.1.2 suffer from content spoofing in the dav app. The exception message displayed on the DAV endpoints contained partially user-controllable input leading to a potential misrepresentation of information.

Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.0.6 and 9.1.2 suffer from content spoofing in the files app. The location bar in the files app was not verifying the passed parameters. An attacker could craft an invalid link to a fake directory structure and use this to display an attacker-controlled error message to the user.

Nextcloud Server before 10.0.1 & ownCloud Server before 9.0.6 and 9.1.2 suffer from Reflected XSS in the Gallery application. The gallery app was not properly sanitizing exception messages from the Nextcloud/ownCloud server. Due to an endpoint where an attacker could influence the error message, this led to a reflected Cross-Site-Scripting vulnerability.

Nextcloud Server before 10.0.1 & ownCloud Server before 9.0.6 and 9.1.2 suffer from Stored XSS in CardDAV image export. The CardDAV image export functionality as implemented in Nextcloud/ownCloud allows the download of images stored within a vCard. Due to not performing any kind of verification on the image content this is prone to a stored Cross-Site Scripting attack.

Nextcloud Server before 9.0.54 and 10.0.0 suffers from an improper authorization check on removing shares. The Sharing Backend as implemented in Nextcloud does differentiate between shares to users and groups. In case of a received group share, users should be able to unshare the file to themselves but not to the whole group. The previous API implementation simply unshared the file to all users in the group.

Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.1.2, 9.0.6, and 8.2.9 suffer from SMB User Authentication Bypass. Nextcloud/ownCloud include an optional and not by default enabled SMB authentication component that allows authenticating users against an SMB server. This backend is implemented in a way that tries to connect to a SMB server and if that succeeded consider the user logged-in. The backend did not properly take into account SMB servers that have any kind of anonymous auth configured. This is the default on SMB servers nowadays and allows an unauthenticated attacker to gain access to an account without valid credentials. Note: The SMB backend is disabled by default and requires manual configuration in the Nextcloud/ownCloud config file. If you have not configured the SMB backend then you're not affected by this vulnerability.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are not properly verifying restore privileges when restoring a file. The restore capability of Nextcloud/ownCloud was not verifying whether a user has only read-only access to a share. Thus a user with read-only access was able to restore old versions.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are not properly verifying edit check permissions on WebDAV copy actions. The WebDAV endpoint was not properly checking the permission on a WebDAV COPY action. This allowed an authenticated attacker with access to a read-only share to put new files in there. It was not possible to modify existing files.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are vulnerable to a content-spoofing attack in the files app. The location bar in the files app was not verifying the passed parameters. An attacker could craft an invalid link to a fake directory structure and use this to display an attacker-controlled error message to the user.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are vulnerable to a log pollution vulnerability potentially leading to a local XSS. The download log functionality in the admin screen is delivering the log in JSON format to the end-user. The file was delivered with an attachment disposition forcing the browser to download the document. However, Firefox running on Microsoft Windows would offer the user to open the data in the browser as an HTML document. Thus any injected data in the log would be executed.

Cross-site scripting (XSS) vulnerability in share.js in the gallery application in ownCloud Server before 9.0.4 and Nextcloud Server before 9.0.52 allows remote authenticated users to inject arbitrary web script or HTML via a crafted directory name.