discourse CVE Vulnerabilities & Metrics

Discourse is an open source platform for community discussion. An attacker can execute arbitrary JavaScript on users' browsers by sending a maliciously crafted chat message and replying to it. This issue only affects sites with CSP disabled. This problem is patched in the latest version of Discourse. All users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled on the forum. Users who do upgrade should also consider enabling a CSP as well as a proactive measure.

Discourse is an open source platform for community discussion. Users can see topics with a hidden tag if they know the label/name of that tag. This issue has been patched in the latest stable, beta and tests-passed version of Discourse. All users area are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open source platform for community discussion. A maliciously crafted email address could allow an attacker to bypass domain-based restrictions and gain access to private sites, categories and/or groups. This issue has been patched in the latest stable, beta and tests-passed version of Discourse. All users area are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open source platform for community discussion. A user can create a post with many replies, and then attempt to fetch them all at once. This can potentially reduce the availability of a Discourse instance. This problem has been patched in the latest version of Discourse. All users area are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse Calendar plugin adds the ability to create a dynamic calendar in the first post of a topic to Discourse. Rendering event names can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse’s default Content Security Policy. The issue is patched in version 0.5 of the Discourse Calendar plugin.

discourse-calendar is a discourse plugin which adds the ability to create a dynamic calendar in the first post of a topic. The limit on region value length is too generous. This allows a malicious actor to cause a Discourse instance to use excessive bandwidth and disk space. This issue has been patched in main the main branch. There are no workarounds for this vulnerability. Please upgrade as soon as possible.

Discourse is an open source discussion platform. Prior to 3.2.5 and 3.3.0.beta5, the vulnerability allows an attacker to inject iframes from any domain, bypassing the intended restrictions enforced by the allowed_iframes setting. This vulnerability is fixed in 3.2.5 and 3.3.0.beta5.

Discourse is an open source discussion platform. Prior to 3.2.5 and 3.3.0.beta5, crafting requests to submit very long tag group names can reduce the availability of a Discourse instance. This vulnerability is fixed in 3.2.5 and 3.3.0.beta5.

Discourse is an open source discussion platform. Prior to 3.2.3 and 3.3.0.beta3, improperly sanitized Onebox data could lead to an XSS vulnerability in some situations. This vulnerability only affects Discourse instances which have disabled the default Content Security Policy. This vulnerability is fixed in 3.2.3 and 3.3.0.beta3.

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches, a malicious actor could get the FastImage library to redirect requests to an internal Discourse IP. This issue is patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches. No known workarounds are available.

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches, moderators using the review queue to review users may see a users email address even when the Allow moderators to view email addresses setting is disabled. This issue is patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches. As possible workarounds, either prevent moderators from accessing the review queue or disable the approve suspect users site setting and the must approve users site setting to prevent users from being added to the review queue.

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch, version 3.3.0.beta3 on the `beta` branch, and version 3.3.0.beta4-dev on the `tests-passed` branch, a rogue staff user could suspend other staff users preventing them from logging in to the site. The issue is patched in version 3.2.3 on the `stable` branch, version 3.3.0.beta3 on the `beta` branch, and version 3.3.0.beta4-dev on the `tests-passed` branch. No known workarounds are available.

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch, an attacker can execute arbitrary JavaScript on users’ browsers by posting a specific URL containing maliciously crafted meta tags. This issue only affects sites with Content Security Polic (CSP) disabled. The problem has been patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch. As a workaround, ensure CSP is enabled on the forum.

Discourse Calendar adds the ability to create a dynamic calendar in the first post of a topic on the open-source discussion platform Discourse. Prior to version 0.4, event invitees created in topics in private categories or PMs (private messages) can be retrieved by anyone, even if they're not logged in. This problem is resolved in version 0.4 of the discourse-calendar plugin. While no known workaround is available, putting the site behind `login_required` will disallow this endpoint to be used by anonymous users, but logged in users can still get the list of invitees in the private topics.

Discourse Calendar adds the ability to create a dynamic calendar in the first post of a topic on Discourse. Uninvited users are able to gain access to private events by crafting a request to update their attendance. This problem is resolved in commit dfc4fa15f340189f177a1d1ab2cc94ffed3c1190. As a workaround, one may use post visibility to limit access.

discourse-group-membership-ip-block is a discourse plugin that adds support for adding users to groups based on their IP address. discourse-group-membership-ip-block was sending all group custom fields to the client, including group custom fields from other plugins which may expect their custom fields to remain secret.

Discourse is an open-source discussion platform. Improperly sanitized user input could lead to an XSS vulnerability in some situations. This vulnerability only affects Discourse instances which have disabled the default Content Security Policy. The vulnerability is patched in 3.1.5 and 3.2.0.beta5. As a workaround, ensure Content Security Policy is enabled and does not include `unsafe-inline`.

Discourse is a platform for community discussion. For fields that are client editable, limits on sizes are not imposed. This allows a malicious actor to cause a Discourse instance to use excessive disk space and also often excessive bandwidth. The issue is patched 3.1.4 and 3.2.0.beta4.

Discourse is a platform for community discussion. Under very specific circumstances, secure upload URLs associated with posts can be accessed by guest users even when login is required. This vulnerability has been patched in 3.2.0.beta4 and 3.1.4.

Discourse-reactions is a plugin that allows user to add their reactions to the post. Data about a user's reaction notifications could be exposed. This vulnerability was patched in commit 2c26939.

Discourse is a platform for community discussion. The message serializer uses the full list of expanded chat mentions (@all and @here) which can lead to a very long array of users. This issue was patched in versions 3.1.4 and beta 3.2.0.beta5.

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, the embedding feature is susceptible to server side request forgery. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. As a workaround, disable the Embedding feature.

Discourse is an open source platform for community discussion. In versions 3.1.0 through 3.1.2 of the `stable` branch and versions 3.1.0,beta6 through 3.2.0.beta2 of the `beta` and `tests-passed` branches, Redis memory can be depleted by crafting a site with an abnormally long favicon URL and drafting multiple posts which Onebox it. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, some links can inject arbitrary HTML tags when rendered through our Onebox engine. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, some theme components allow users to add svgs with unlimited `height` attributes, and this can affect the availability of subsequent replies in a topic. Most Discourse instances are unaffected, only instances with the svgbob or the mermaid theme component are within scope. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. As a workaround, disable or remove the relevant theme components.

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, there is an edge case where a bookmark reminder is sent and an unread notification is generated, but the underlying bookmarkable (e.g. post, topic, chat message) security has changed, making it so the user can no longer access the underlying resource. As of version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, bookmark reminders are now no longer sent if the user does not have access to the underlying bookmarkable, and also the unread bookmark notifications are always filtered by access. There are no known workarounds.

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, if a user has been quoted and uses a `|` in their full name, they might be able to trigger a bug that generates a lot of duplicate content in all the posts they've been quoted by updating their full name again. Version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches contain a patch for this issue. No known workaround exists, although one can stop the "bleeding" by ensuring users only use alphanumeric characters in their full name field.

Discourse is an open source platform for community discussion. New chat messages can be read by making an unauthenticated POST request to MessageBus. This issue is patched in the 3.1.1 stable and 3.2.0.beta2 versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open source platform for community discussion. User summaries are accessible for anonymous users even when `hide_user_profiles_from_public` is enabled. This problem has been patched in the 3.1.1 stable and 3.2.0.beta2 version of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open source platform for community discussion. A malicious request can cause production log files to quickly fill up and thus result in the server running out of disk space. This problem has been patched in the 3.1.1 stable and 3.2.0.beta2 versions of Discourse. It is possible to temporarily work around this problem by reducing the `client_max_body_size nginx directive`. `client_max_body_size` will limit the size of uploads that can be uploaded directly to the server.

Discourse is an open source platform for community discussion. Attackers with details specific to a poll in a topic can use the `/polls/grouped_poll_results` endpoint to view the content of options in the poll and the number of votes for groups of poll participants. This impacts private polls where the results were intended to only be viewable by authorized users. This issue is patched in the 3.1.1 stable and 3.2.0.beta2 versions of Discourse. There is no workaround for this issue apart from upgrading to the fixed version.

Discourse is an open source platform for community discussion. Improper escaping of user input allowed for Cross-site Scripting attacks via the digest email preview UI. This issue only affects sites with CSP disabled. This issue has been patched in the 3.1.1 stable release as well as the 3.2.0.beta1 release. Users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled on the forum.

dicourse-calendar is a plugin for the Discourse messaging platform which adds the ability to create a dynamic calendar in the first post of a topic. Improper escaping of event titles could lead to Cross-site Scripting (XSS) within the 'email preview' UI when a site has CSP disabled. Having CSP disabled is a non-default configuration, so the vast majority of sites are unaffected. This problem is resolved in the latest version of the discourse-calendar plugin. Users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled on the forum.

Discourse is an open source community platform. In affected versions any user can create a topic and add arbitrary custom fields to a topic. The severity of this vulnerability depends on what plugins are installed and how the plugins uses topic custom fields. For a default Discourse installation with the default plugins, this vulnerability has no impact. The problem has been patched in the latest version of Discourse. Users are advised to update to version 3.1.1 if they are on the stable branch or 3.2.0.beta2 if they are on the beta branch. Users unable to upgrade should disable any plugins that access topic custom fields.

Discourse-jira is a Discourse plugin allows Jira projects, issue types, fields and field options will be synced automatically. An administrator user can make an SSRF attack by setting the Jira URL to an arbitrary location and enabling the `discourse_jira_verbose_log` site setting. A moderator user could manipulate the request path to the Jira API, allowing them to perform arbitrary GET requests using the Jira API credentials, potentially with elevated permissions, used by the application.

discourse-encrypt is a plugin that provides a secure communication channel through Discourse. Improper escaping of encrypted topic titles could lead to a cross site scripting (XSS) issue when a site has content security policy (CSP) headers disabled. Having CSP disabled is a non-default configuration, and having it disabled with discourse-encrypt installed will result in a warning in the Discourse admin dashboard. This has been fixed in commit `9c75810af9` which is included in the latest version of the discourse-encrypt plugin. Users are advised to upgrade. Users unable to upgrade should ensure that CSP headers are enabled and properly configured.

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, a malicious admin could create extremely large icons sprites, which would then be cached in each server process. This may cause server processes to be killed and lead to downtime. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. This is only a concern for multisite installations. No action is required when the admins are trusted.

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, importing a remote theme loads their assets into memory without enforcing limits for file size or number of files. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, a malicious user could add a 2FA or security key with a carefully crafted name to their account and cause a denial of service for other users. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, a malicious user can create an unlimited number of drafts with very long draft keys which may end up exhausting the resources on the server. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, information about restricted-visibility topic tags could be obtained by unauthorized users. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches.

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, in multiple controller actions, Discourse accepts limit params but does not impose any upper bound on the values being accepted. Without an upper bound, the software may allow arbitrary users to generate DB queries which may end up exhausting the resources on the server. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. There are no known workarounds for this vulnerability.

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, a malicious user can prevent the defer queue from proceeding promptly on sites hosted in the same multisite installation. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. There are no known workarounds for this vulnerability. Users of multisite configurations should upgrade.

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, a malicious user can edit a post in a topic and cause a DoS with a carefully crafted edit reason. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. There are no known workarounds for this vulnerability.

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, more users than permitted could be created from invite links. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. As a workaround, use restrict to email address invites.

Discourse is an open source discussion platform. Prior to version 3.1.0.beta7 of the `beta` and `tests-passed` branches, a CSP (Content Security Policy) nonce reuse vulnerability was discovered could allow cross-site scripting (XSS) attacks to bypass CSP protection for anonymous (i.e. unauthenticated) users. There are no known XSS vectors at the moment, but should one be discovered, this vulnerability would allow the XSS attack to bypass CSP and execute successfully. This vulnerability isn't applicable to logged-in users. Version 3.1.0.beta7 contains a patch. The stable branch doesn't have this vulnerability. A workaround to prevent the vulnerability is to disable Google Tag Manager, i.e., unset the `gtm container id` setting.

Discourse is an open source discussion platform. In affected versions a request to create or update custom sidebar section can cause a denial of service. This issue has been patched in commit `52b003d915`. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open source discussion platform. When editing a topic, there is a vulnerability that enables a user to bypass the topic title validations for things like title length, number of emojis in title and blank topic titles. The issue is patched in the latest stable, beta and tests-passed version of Discourse.

Discourse is an open source discussion platform. A CSP (Content Security Policy) nonce reuse vulnerability could allow XSS attacks to bypass CSP protection. There are no known XSS vectors at the moment, but should one be discovered, this vulnerability would allow the XSS attack to completely bypass CSP. The vulnerability is patched in the latest tests-passed, beta and stable branches.

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, an attacker could use the new topics dismissal endpoint to reveal the number of topics recently created (but not the actual content thereof) in categories they didn't have access to. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, multiple duplicate topics could be created if topic embedding is enabled. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. As a workaround, disable topic embedding if it has been enabled.

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, the lack of restrictions on the iFrame tag makes it easy for an attacker to exploit the vulnerability and hide subsequent comments from other users. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, if a site has modified their general category permissions, they could be set back to the default. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. A workaround, only if you are modifying the general category permissions, is to use a new category for the same purpose.

Discourse-reactions is a plugin that allows user to add their reactions to the post in the Discourse messaging platform. In affected versions data about what reactions were performed on a post in a private topic could be leaked. This issue has been addressed in version 0.3. Users are advised to upgrade. Users unable to upgrade should disable the discourse-reactions plugin to fully mitigate the issue.

Discourse is an open source platform for community discussion. In affected versions a user logged as an administrator can call arbitrary methods on the `SiteSetting` class, notably `#clear_cache!` and `#notify_changed!`, which when done on a multisite instance, can affect the entire cluster resulting in a denial of service. Users not running in multisite environments are not affected. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open source platform for community discussion. Due to the improper sanitization of SVG files, an attacker can execute arbitrary JavaScript on the users’ browsers by uploading a crafted SVG file. This issue is patched in the latest stable and tests-passed versions of Discourse. Users are advised to upgrade. For users unable to upgrade there are two possible workarounds: enable CDN handing of uploads (and ensure the CDN sanitizes SVG files) or disable SVG file uploads by ensuring that the `authorized extensions` site setting does not include `svg` (or reset that setting to the default, by default Discourse doesn't enable SVG uploads by users).

Discourse is an open source platform for community discussion. This vulnerability is not exploitable on the default install of Discourse. A custom feature must be enabled for it to work at all, and the attacker’s payload must pass the CSP to be executed. However, if an attacker succeeds in embedding Javascript that does pass the CSP, it could result in session hijacking for any users that view the attacker’s post. The vulnerability is patched in the latest tests-passed, beta and stable branches. Users are advised to upgrade. Users unable to upgrade should enable and/or restore your site's CSP to the default one provided with Discourse. Remove any embed-able hosts configured.

Discourse is an open source platform for community discussion. In affected versions a maliciously crafted request from a Discourse administrator can lead to a long-running request and eventual timeout. This has the greatest potential impact in shared hosting environments where admins are untrusted. This issue has been addressed in versions 3.0.3 and 3.1.0.beta4. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open-source discussion platform. Prior to version 3.1.0.beta3 of the `beta` and `tests-passed` branches, some user provided URLs were being passed to FastImage without SSRF protection. Insufficient protections could enable attackers to trigger outbound network connections from the Discourse server to private IP addresses. This affects any site running the `tests-passed` or `beta` branches versions 3.1.0.beta2 and prior. This issue is patched in version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.1.0.beta3 of the `beta` and `tests-passed` branches, attackers are able to bypass Discourse's server-side request forgery (SSRF) protection for private IPv4 addresses by using a IPv4-mapped IPv6 address. The issue is patched in the latest beta and tests-passed version of Discourse. version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.0.2 of the `stable` branch and version 3.1.0.beta3 of the `beta` and `tests-passed` branches, a user logged as an administrator can request backups multiple times, which will eat up all the connections to the DB. If this is done on a site using multisite, then it can affect the whole cluster. The vulnerability is patched in version 3.0.2 of the `stable` branch and version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches, a maliciously crafted URL can be included in a user's full name field to to carry out cross-site scripting attacks on sites with a disabled or overly permissive CSP (Content Security Policy). Discourse's default CSP prevents this vulnerability. The vulnerability is patched in version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches. As a workaround, enable and/or restore your site's CSP to the default one provided with Discourse.

Discourse is an open-source discussion platform. Between versions 3.1.0.beta2 and 3.1.0.beta3 of the `tests-passed` branch, editing or responding to a chat message containing malicious content could lead to a cross-site scripting attack. This issue is patched in version 3.1.0.beta3 of the `tests-passed` branch. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches, the count of topics displayed for a tag is a count of all regular topics regardless of whether the topic is in a read restricted category or not. As a result, any users can technically poll a sensitive tag to determine if a new topic is created in a category which the user does not have excess to. In version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches, the count of topics displayed for a tag defaults to only counting regular topics which are not in read restricted categories. Staff users will continue to see a count of all topics regardless of the topic's category read restrictions.

Discourse is an open-source messaging platform. In versions 3.0.1 and prior on the `stable` branch and versions 3.1.0.beta2 and prior on the `beta` and `tests-passed` branches, the count of personal messages displayed for a tag is a count of all personal messages regardless of whether the personal message is visible to a given user. As a result, any users can technically poll a sensitive tag to determine if a new personal message is created even if the user does not have access to the personal message. In the patched versions, the count of personal messages tagged with a given tag is hidden by default. To revert to the old behaviour of displaying the count of personal messages for a given tag, an admin may enable the `display_personal_messages_tag_counts` site setting.

discourse-yearly-review is a discourse plugin which publishes an automated Year in Review topic. In affected versions a user present in a yearly review topic that is then anonymised will still have some data linked to its original account. This issue has been patched in commit `b3ab33bbf7` which is included in the latest version of the Discourse Yearly Review plugin. Users are advised to upgrade. Users unable to upgrade may disable the `yearly_review_enabled` setting to fully mitigate the issue. Also, it's possible to edit the anonymised user's old data in the yearly review topics manually.

Discourse is an open source platform for community discussion. Tags that are normally private are showing in metadata. This affects any site running the `tests-passed` or `beta` branches >= 3.1.0.beta2. The issue is patched in the latest `beta` and `tests-passed` version of Discourse.

Discourse is an open source discussion platform. In affected versions a malicious user can cause a regular expression denial of service using a carefully crafted git URL. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. There are no known workarounds for this issue.

Discourse is an open source discussion platform. The embeddable comments can be exploited to create new topics as any user but without any clear title or content. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. As a workaround, disable embeddable comments by deleting all embeddable hosts.

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches, someone can use the `exclude_tag param` to filter out topics and deduce which ones were using a specific hidden tag. This affects any Discourse site using hidden tags in public categories. This issue is patched in version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches. As a workaround, secure any categories that are using hidden tags, change any existing hidden tags to not include private data, or remove any hidden tags currently in use.

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches, a malicious user can cause a regular expression denial of service using a carefully crafted user agent. This issue is patched in version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches, the contents of latest/top routes for restricted tags can be accessed by unauthorized users. This issue is patched in version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches, when submitting a membership request, there is no character limit for the reason provided with the request. This could potentially allow a user to flood the database with a large amount of data. However it is unlikely this could be used as part of a DoS attack, as the paths reading back the reasons are only available to administrators. Starting in version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches, a limit of 280 characters has been introduced for membership requests.

Discourse is an open source platform for community discussion. Versions prior to 3.1.0.beta1 (beta) (tests-passed) are vulnerable to Allocation of Resources Without Limits. Users can create chat drafts of an unlimited length, which can cause a denial of service by generating an excessive load on the server. Additionally, an unlimited number of drafts were loaded when loading the user. This issue has been patched in version 2.1.0.beta1 (beta) and (tests-passed). Users should upgrade to the latest version where a limit has been introduced. There are no workarounds available.

Discourse is an open source platform for community discussion. Versions prior to 3.0.1 (stable), 3.1.0.beta2 (beta), and 3.1.0.beta2 (tests-passed) are subject to Allocation of Resources Without Limits or Throttling. As there is no limit on data contained in a draft, a malicious user can create an arbitrarily large draft, forcing the instance to a crawl. This issue is patched in versions 3.0.1 (stable), 3.1.0.beta2 (beta), and 3.1.0.beta2 (tests-passed). There are no workarounds.

Discourse is an open source platform for community discussion. Versions prior to 2.8.13 (stable), 3.0.0.beta16 (beta) and 3.0.0beta16 (tests-passed), are vulnerable to cross-site Scripting. A maliciously crafted URL can be included in a post to carry out cross-site scripting attacks on sites with disabled or overly permissive CSP (Content Security Policy). Discourse's default CSP prevents this vulnerability. This vulnerability is patched in versions 2.8.13 (stable), 3.0.0.beta16 (beta) and 3.0.0beta16 (tests-passed). As a workaround, enable and/or restore your site's CSP to the default one provided with Discourse.

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, tag descriptions, which can be updated by moderators, can be used for cross-site scripting attacks. This vulnerability can lead to a full XSS on sites which have modified or disabled Discourse’s default Content Security Policy. Versions 2.8.14 and 3.0.0.beta16 contain a patch.

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, pending post titles can be used for cross-site scripting attacks. Pending posts can be created by unprivileged users when a category has the "require moderator approval of all new topics" setting set. This vulnerability can lead to a full XSS on sites which have modified or disabled Discourse’s default Content Security Policy. A patch is available in versions 2.8.14 and 3.0.0.beta16.

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, the number of times a user posted in an arbitrary topic is exposed to unauthorized users through the `/u/username.json` endpoint. The issue is patched in version 2.8.14 and 3.0.0.beta16. There is no known workaround.

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, when a user requests for a password reset link email, then changes their primary email, the old reset email is still valid. When the old reset email is used to reset the password, the Discourse account's primary email would be re-linked to the old email. If the old email address is compromised or has transferred ownership, this leads to an account takeover. This is however mitigated by the SiteSetting `email_token_valid_hours` which is currently 48 hours. Users should upgrade to versions 2.8.14 or 3.0.0.beta15 to receive a patch. As a workaround, lower `email_token_valid_hours ` as needed.

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 2.9.0.beta16 on the `beta` and `tests-passed` branches, users can create posts with raw body longer than the `max_length` site setting by including html comments that are not counted toward the character limit. This issue is patched in versions 2.8.14 and 2.9.0.beta16. There are no known workarounds.

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 2.9.0.beta16 on the `beta` and `tests-passed` branches, parsing posts can be susceptible to regular expression denial of service (ReDoS) attacks. This issue is patched in versions 2.8.14 and 2.9.0.beta16. There are no known workarounds.

In version 2.9.0.beta14 of Discourse, an open-source discussion platform, maliciously embedded urls can leak an admin's digest of recent topics, possibly exposing private information. A patch is available for version 2.9.0.beta15. There are no known workarounds for this issue.

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 2.9.0.beta15 on the `beta` and `tests-passed` branches, recipients of a group SMTP email could see the email addresses of all other users inside the group SMTP topic. Most of the time this is not an issue as they are likely already familiar with one another's email addresses. This issue is patched in versions 2.8.14 and 2.9.0.beta15. The fix is that someone sending emails out via group SMTP to non-staged users masks those emails with blind carbon copy (BCC). Staged users are ones that have likely only interacted with the group via email, and will likely include other people who were CC'd on the original email to the group. As a workaround, disable group SMTP for any groups that have it enabled.

Discourse Mermaid (discourse-mermaid-theme-component) allows users of Discourse, open-source forum software, to create graphs using the Mermaid syntax. Users of discourse-mermaid-theme-component version 1.0.0 who can create posts are able to inject arbitrary HTML on that post. The issue has been fixed on the `main` branch of the GitHub repository, with 1.1.0 named as a patched version. Admins can update the theme component through the admin UI. As a workaround, admins can temporarily disable discourse-mermaid-theme-component.

Discourse is an open-source discussion platform. In version 2.8.13 and prior on the `stable` branch and version 2.9.0.beta14 and prior on the `beta` and `tests-passed` branches, any authenticated user can create an unlisted topic. These topics, which are not readily available to other users, can take up unnecessary site resources. A patch for this issue is available in the `main` branch of Discourse. There are no known workarounds available.

Discourse is an open-source discussion platform. Prior to version 2.8.13 of the `stable` branch and version 2.9.0.beta14 of the `beta` and `tests-passed` branches, unauthorized users may learn of the existence of hidden tags and that they have been applied to topics that they have access to. This issue is patched in version 2.8.13 of the `stable` branch and version 2.9.0.beta14 of the `beta` and `tests-passed` branches. As a workaround, use the `disable_email` site setting to disable all emails to non-staff users.

Discourse is an open-source messaging platform. In versions 2.8.10 and prior on the `stable` branch and versions 2.9.0.beta11 and prior on the `beta` and `tests-passed` branches, users composing malicious messages and navigating to drafts page could self-XSS. This vulnerability can lead to a full XSS on sites which have modified or disabled Discourse’s default Content Security Policy. This issue is patched in the latest stable, beta and tests-passed versions of Discourse.

Discourse is an open-source discussion platform. In stable versions prior to 2.8.12 and beta or tests-passed versions prior to 2.9.0.beta.13, under certain conditions, a user can see notifications for topics they no longer have access to. If there is sensitive information in the topic title, it will therefore have been exposed. This issue is patched in stable version 2.8.12, beta version 2.9.0.beta13, and tests-passed version 2.9.0.beta13. There are no workarounds available.

Discourse is an open-source discussion platform. Prior to version 2.9.0.beta13, users can post chat messages of an unlimited length, which can cause a denial of service for other users when posting huge amounts of text. Users should upgrade to version 2.9.0.beta13, where a limit has been introduced. No known workarounds are available.

Discourse-calendar is a plugin for the Discourse messaging platform which adds the ability to create a dynamic calendar in the first post of a topic. Members of private groups or public groups with private members can be listed by users, who can create and edit post events. This vulnerability only affects sites which have discourse post events enabled. This issue has been patched in commit `ca5ae3e7e` which will be included in future releases. Users unable to upgrade should disable the `discourse_post_event_enabled` setting to fully mitigate the issue. Also, it's possible to prevent regular users from using this vulnerability by removing all groups from the `discourse_post_event_allowed_on_groups` but note that moderators will still be able to use it.

Discourse is the an open source discussion platform. In some rare cases users redeeming an invitation can be added as a participant to several private message topics that they should not be added to. They are not notified of this, it happens transparently in the background. This issue has been resolved in commit `a414520742` and will be included in future releases. Users are advised to upgrade. Users are also advised to set `SiteSetting.max_invites_per_day` to 0 until the patch is installed.

Discourse is a platform for community discussion. Under certain conditions, a user badge may have been awarded based on a user's activity in a topic with restricted access. Before this vulnerability was disclosed, the topic title of the topic associated with the user badge may be viewed by any user. If there are sensitive information in the topic title, it will therefore have been exposed. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. There are currently no known workarounds available.

Discourse is a platform for community discussion. Users who receive an invitation link that is not scoped to a single email address can enter any non-admin user's email and gain access to their account when accepting the invitation. All users should upgrade to the latest version. A workaround is temporarily disabling invitations with `SiteSetting.max_invites_per_day = 0` or scope them to individual email addresses.

Discourse is a platform for community discussion. A malicious admin could use this vulnerability to perform port enumeration on the local host or other hosts on the internal network, as well as against hosts on the Internet. Latest `stable`, `beta`, and `test-passed` versions are now patched. As a workaround, self-hosters can use `DISCOURSE_BLOCKED_IP_BLOCKS` env var (which overrides `blocked_ip_blocks` setting) to stop webhooks from accessing private IPs.

Discourse Patreon enables syncronization between Discourse Groups and Patreon rewards. On sites with Patreon login enabled, an improper authentication vulnerability could be used to take control of a victim's forum account. This vulnerability is patched in commit number 846d012151514b35ce42a1636c7d70f6dcee879e of the discourse-patreon plugin. Out of an abundance of caution, any Discourse accounts which have logged in with an unverified-email Patreon account will be logged out and asked to verify their email address on their next login. As a workaround, disable the patreon integration and log out all users with associated Patreon accounts.

discourse-chat is a plugin for the Discourse message board which adds chat functionality. In versions prior to 0.9 some places render a chat channel's name and description in an unsafe way, allowing staff members to cause an cross site scripting (XSS) attack by inserting unsafe HTML into them. Version 0.9 has addressed this issue. Users are advised to upgrade. There are no known workarounds for this issue.

DiscoTOC is a Discourse theme component that generates a table of contents for topics. Users that can create topics in TOC-enabled categories (and have sufficient trust level - configured in component's settings) are able to inject arbitrary HTML on that topic's page. The issue has been fixed on the `main` branch. Admins can update the theme component through the admin UI (Customize -> Themes -> Components -> DiscoTOC -> Check for Updates). Alternatively, admins can temporarily disable the DiscoTOC theme component.

Discourse is an open source discussion platform. Starting with version 2.9.0.beta5 and prior to version 2.9.0.beta10, an incomplete quote can generate a JavaScript error which will crash the current page in the browser in some cases. Version 2.9.0.beta10 added a fix and tests to ensure incomplete quotes won't break the app. As a workaround, the quote can be fixed via the rails console.

Discourse is an open source discussion platform. In versions prior to 2.8.9 on the `stable` branch and prior to 2.9.0.beta10 on the `beta` and `tests-passed` branches, a malicious actor can add large payloads of text into the Location and Website fields of a user profile, which causes issues for other users when loading that profile. A fix to limit the length of user input for these fields is included in version 2.8.9 on the `stable` branch and version 2.9.0.beta10 on the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open source discussion platform. In versions prior to 2.8.9 on the `stable` branch and prior to 2.9.0.beta10 on the `beta` and `tests-passed` branches, a moderator can create new and edit existing themes by using the API when they should not be able to do so. The problem is patched in version 2.8.9 on the `stable` branch and version 2.9.0.beta10 on the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse is an open source discussion platform. In versions prior to 2.8.9 on the `stable` branch and prior to 2.9.0.beta10 on the `beta` and `tests-passed` branches, admins can upload a maliciously crafted Zip or Gzip Tar archive to write files at arbitrary locations and trigger remote code execution. The problem is patched in version 2.8.9 on the `stable` branch and version 2.9.0.beta10 on the `beta` and `tests-passed` branches. There are no known workarounds.

Discourse-Chat is an asynchronous messaging plugin for the Discourse open-source discussion platform. Users of Discourse Chat can be affected by admin users inserting HTML into chat titles and descriptions, causing a Cross-Site Scripting (XSS) attack. Version 0.9 contains a patch for this issue.

Discourse through 2.8.7 allows admins to send invitations to arbitrary email addresses at an unlimited rate.

Discourse is the an open source discussion platform. In affected versions an email activation route can be abused to send mass spam emails. A fix has been included in the latest stable, beta and tests-passed versions of Discourse which rate limits emails. Users are advised to upgrade. Users unable to upgrade should manually rate limit email.

Discourse is the an open source discussion platform. In affected versions a maliciously crafted request for static assets could cause error responses to be cached by Discourse's default NGINX proxy configuration. A corrected NGINX configuration is included in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Discourse is an open source discussion platform. Under certain conditions, a logged in user can redeem an invite with an email that either doesn't match the invite's email or does not adhere to the email domain restriction of an invite link. The impact of this flaw is aggravated when the invite has been configured to add the user that accepts the invite into restricted groups. Once a user has been incorrectly added to a restricted group, the user may then be able to view content which that are restricted to the respective group. Users are advised to upgrade to the current stable releases. There are no known workarounds to this issue.

discourse-chat is a chat plugin for the Discourse application. Versions prior to 0.4 are vulnerable to an exposure of sensitive information, where an attacker who knows the message ID for a channel they do not have access to can view that message using the chat message lookup endpoint, primarily affecting direct message channels. There are no known workarounds for this issue, and users are advised to update the plugin.

Discourse is an open-source discussion platform. Prior to version 2.8.4 in the `stable` branch and version `2.9.0.beta5` in the `beta` and `tests-passed` branches, banner topic data is exposed on login-required sites. This issue is patched in version 2.8.4 in the `stable` branch and version `2.9.0.beta5` in the `beta` and `tests-passed` branches of Discourse. As a workaround, one may disable banners.

Discourse Calendar is a calendar plugin for Discourse, an open-source messaging app. Prior to version 1.0.1, parsing and rendering of Event names can be susceptible to cross-site scripting (XSS) attacks. This vulnerability only affects sites which have modified or disabled Discourse’s default Content Security Policy. This issue is patched in version 1.0.1 of the Discourse Calendar plugin. As a workaround, ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.

Discourse is an open source platform for community discussion. Prior to version 2.8.4 on the `stable` branch and 2.9.0beta5 on the `beta` and `tests-passed` branches, inviting users on sites that use single sign-on could bypass the `must_approve_users` check and invites by staff are always approved automatically. The issue is patched in Discourse version 2.8.4 on the `stable` branch and version `2.9.0.beta5` on the `beta` and `tests-passed` branches. As a workaround, disable invites or increase `min_trust_level_to_allow_invite` to reduce the attack surface to more trusted users.

Discourse is an open source platform for community discussion. A category's group permissions settings can be viewed by anyone that has access to the category. As a result, a normal user is able to see whether a group has read/write permissions in the category even though the information should only be available to the users that can manage a category. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. There are no workarounds for this problem.

Discourse is an open source platform for community discussion. In affected versions an attacker can poison the cache for anonymous (i.e. not logged in) users, such that the users are shown the crawler view of the site instead of the HTML page. This can lead to a partial denial-of-service. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. There are no known workarounds for this issue.

Discourse is an open source platform for community discussion. In stable versions prior to 2.8.3 and beta versions prior 2.9.0.beta4 erroneously expose groups. When a group with restricted visibility has been used to set the permissions of a category, the name of the group is leaked to any user that is able to see the category. To workaround the problem, a site administrator can remove groups with restricted visibility from any category's permissions setting.

Discourse is an open source discussion platform. Versions 2.8.2 and prior in the `stable` branch, 2.9.0.beta3 and prior in the `beta` branch, and 2.9.0.beta3 and prior in the `tests-passed` branch are vulnerable to a data leak. Users can request an export of their own activity. Sometimes, due to category settings, they may have category membership for a secure category. The name of this secure category is shown to the user in the export. The same thing occurs when the user's post has been moved to a secure category. A patch for this issue is available in the `main` branch of Discourse's GitHub repository and is anticipated to be part of future releases.

Discourse is an open source discussion platform. In versions prior to 2.8.1 in the `stable` branch, 2.9.0.beta2 in the `beta` branch, and 2.9.0.beta2 in the `tests-passed` branch, users can trigger a Denial of Service attack by posting a streaming URL. Parsing Oneboxes in the background job trigger an infinite loop, which cause memory leaks. This issue is patched in version 2.8.1 of the `stable` branch, 2.9.0.beta2 of the `beta` branch, and 2.9.0.beta2 of the `tests-passed` branch. As a workaround, disable onebox in admin panel completely or specify allow list of domains that will be oneboxed.

Discourse is an open source discussion platform. Discourse groups can be configured with varying visibility levels for the group as well as the group members. By default, a newly created group has its visibility set to public and the group's members visibility set to public as well. However, a group's visibility and the group's members visibility can be configured such that it is restricted to logged on users, members of the group or staff users. A vulnerability has been discovered in versions prior to 2.7.13 and 2.8.0.beta11 where the group advanced search option does not respect the group's visibility and members visibility level. As such, a group with restricted visibility or members visibility can be revealed through search with the right search option. This issue is patched in `stable` version 2.7.13, `beta` version 2.8.0.beta11, and `tests-passed` version 2.8.0.beta11 versions of Discourse. There are no workarounds aside from upgrading.

Discourse is an open source discussion platform. Versions prior to 2.7.13 in `stable`, 2.8.0.beta11 in `beta`, and 2.8.0.beta11 in `tests-passed` allow some users to log in to a community before they should be able to do so. A user invited via email to a forum with `must_approve_users` enabled is going to be automatically logged in, bypassing the check that does not allow unapproved users to sign in. They will be able to do everything an approved user can do. If they logout, they cannot log back in. This issue is patched in the `stable` version 2.7.13, `beta` version 2.8.0.beta11, and `tests-passed` version 2.8.0.beta11. One may disable invites as a workaround. Administrators can increase `min_trust_level_to_allow_invite` to reduce the attack surface to more trusted users.

Discourse is an open source discussion platform. Prior to version 2.8.0.beta11 in the `tests-passed` branch, version 2.8.0.beta11 in the `beta` branch, and version 2.7.13 in the `stable` branch, the bios of users who made their profiles private were still visible in the `<meta>` tags on their users' pages. The problem is patched in `tests-passed` version 2.8.0.beta11, `beta` version 2.8.0.beta11, and `stable` version 2.7.13 of Discourse.

Discourse is an open source platform for community discussion. In affected versions when composing a message from topic the composer user suggestions reveals whisper participants. The issue has been patched in stable version 2.7.13 and beta version 2.8.0.beta11. There is no workaround for this issue and users are advised to upgrade.

Discourse is an open source platform for community discussion. In affected versions admins users can trigger a Denial of Service attack via the `/message-bus/_diagnostics` path. The impact of this vulnerability is greater on multisite Discourse instances (where multiple forums are served from a single application server) where any admin user on any of the forums are able to visit the `/message-bus/_diagnostics` path. The problem has been patched. Please upgrade to 2.8.0.beta10 or 2.7.12. No workarounds for this issue exist.

message_bus is a messaging bus for Ruby processes and web clients. In versions prior to 3.3.7 users who deployed message bus with diagnostics features enabled (default off) are vulnerable to a path traversal bug, which could lead to disclosure of secret information on a machine if an unintended user were to gain access to the diagnostic route. The impact is also greater if there is no proxy for your web application as the number of steps up the directories is not bounded. For deployments which uses a proxy, the impact varies. For example, If a request goes through a proxy like Nginx with `merge_slashes` enabled, the number of steps up the directories that can be read is limited to 3 levels. This issue has been patched in version 3.3.7. Users unable to upgrade should ensure that MessageBus::Diagnostics is disabled.

discourse-footnote is a library providing footnotes for posts in Discourse. ### Impact When posting an inline footnote wrapped in `<a>` tags (e.g. `<a>^[footnote]</a>`, the resulting rendered HTML would include a nested `<a>`, which is stripped by Nokogiri because it is not valid. This then caused a javascript error on topic pages because we were looking for an `<a>` element inside the footnote reference span and getting its ID, and because it did not exist we got a null reference error in javascript. Users are advised to update to version 0.2. As a workaround editing offending posts from the rails console or the database console for self-hosters, or disabling the plugin in the admin panel can mitigate this issue.

Discourse is an open source discussion platform. In affected versions an attacker can poison the cache for anonymous (i.e. not logged in) users, such that the users are shown a JSON blob instead of the HTML page. This can lead to a partial denial-of-service. This issue is patched in the latest stable, beta and tests-passed versions of Discourse.

Discourse is an open source discussion platform. In affected versions a vulnerability in the Polls feature allowed users to vote multiple times in a single-option poll. The problem is patched in the latest tests-passed, beta and stable versions of Discourse

Discourse is an open source discussion platform. In affected versions a vulnerability affects users of tag groups who use the "Tags are visible only to the following groups" feature. A tag group may only allow a certain group (e.g. staff) to view certain tags. Users who were tracking or watching the tags via /preferences/tags, then have their staff status revoked will still see notifications related to the tag, but will not see the tag on each topic. This issue has been patched in stable version 2.7.11. Users are advised to upgrade as soon as possible.

Discourse is a platform for community discussion. In affected versions a maliciously crafted request could cause an error response to be cached by intermediate proxies. This could cause a loss of confidentiality for some content. This issue is patched in the latest stable, beta and tests-passed versions of Discourse.

rails_multisite provides multi-db support for Rails applications. In affected versions this vulnerability impacts any Rails applications using `rails_multisite` alongside Rails' signed/encrypted cookies. Depending on how the application makes use of these cookies, it may be possible for an attacker to re-use cookies on different 'sites' within a multi-site Rails application. The issue has been patched in v4 of the `rails_multisite` gem. Note that this upgrade will invalidate all previous signed/encrypted cookies. The impact of this invalidation will vary based on the application architecture.

Discourse is an open source platform for community discussion. In affected versions maliciously crafted requests could lead to remote code execution. This resulted from a lack of validation in subscribe_url values. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. To workaround the issue without updating, requests with a path starting /webhooks/aws path could be blocked at an upstream proxy.

Discourse-reactions is a plugin for the Discourse platform that allows user to add their reactions to the post. In affected versions reactions given by user to secure topics and private messages are visible. This issue is patched in version 0.2 of discourse-reaction. Users who are unable to update are advised to disable the Discourse-reactions plugin in admin panel.

Discourse is an open source discussion platform. There is a cross-site scripting (XSS) vulnerability in versions 2.7.7 and earlier of the `stable` branch, versions 2.8.0.beta6 and earlier of the `beta` branch, and versions 2.8.0.beta6 and earlier of the `tests-passed` branch. Rendering of some error messages that contain user input can be susceptible to XSS attacks. This vulnerability only affects sites which have blocked watched words that contain HTML tags, modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. As a workaround, avoid modifying or disabling Discourse’s default Content Security Policy, and blocking watched words containing HTML tags.

Server Side Request Forgery (SSRF) vulnerability exists in Discourse 2.3.2 and 2.6 via the email function. When writing an email in an editor, you can upload pictures of remote websites.

Discourse is a platform for community discussion. In affected versions any private message that includes a group had its title and participating user exposed to users that do not have access to the private messages. However, access control for the private messages was not compromised as users were not able to view the posts in the leaked private message despite seeing it in their inbox. The problematic commit was reverted around 32 minutes after it was made. Users are encouraged to upgrade to the latest commit if they are running Discourse against the `tests-passed` branch.

Discourse is an open source platform for community discussion. In affected versions category names can be used for Cross-site scripting(XSS) attacks. This is mitigated by Discourse's default Content Security Policy and this vulnerability only affects sites which have modified or disabled or changed Discourse's default Content Security Policy have allowed for moderators to modify categories. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.

Discourse is an open-source platform for community discussion. In Discourse before versions 2.7.8 and 2.8.0.beta5, a user's read state for a topic such as the last read post number and the notification level is exposed.

Discourse is an open-source platform for community discussion. In Discourse before versions 2.7.8 and 2.8.0.beta4, when adding additional email addresses to an existing account on a Discourse site an email token is generated as part of the email verification process. Deleting the additional email address does not invalidate an unused token which can then be used in other contexts, including reseting a password.

Discourse is an open source discussion platform. In versions prior to 2.7.8 rendering of d-popover tooltips can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable` 2.7.8 version of Discourse. As a workaround users may ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.

Discourse is an open source discussion platform. In versions prior to 2.7.7 there are two bugs which led to the post creator of a whisper post being revealed to non-staff users. 1: Staff users that creates a whisper post in a personal message is revealed to non-staff participants of the personal message even though the whisper post cannot be seen by them. 2: When a whisper post is before the last post in a post stream, deleting the last post will result in the creator of the whisper post to be revealed to non-staff users as the last poster of the topic.

Discourse is an open-source discussion platform. In Discourse versions 2.7.5 and prior, parsing and rendering of YouTube Oneboxes can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse's default Content Security Policy. The issue is patched in `stable` version 2.7.6, `beta` version 2.8.0.beta3, and `tests-passed` version 2.8.0.beta3. As a workaround, ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.

In Discourse 2.7.0 through beta1, a rate-limit bypass leads to a bypass of the 2FA requirement for certain forms.

Discourse 2.3.2 sends the CSRF token in the query string.

Discourse before 2.3.0 and 2.4.x before 2.4.0.beta3 lacks a confirmation screen when logging in via an email link.

Discourse before 2.3.0 and 2.4.x before 2.4.0.beta3 lacks a confirmation screen when logging in via a user-api OTP.