CVE-2022-39339 Vulnerability Analysis & Exploit Details

CVE-2022-39339 Vulnerability Summary

CVE-2022-39339: user_oidc is an OpenID Connect user backend for Nextcloud. In versions prior to 1.2.1 sensitive information such as the OIDC client credentials and tokens are sent in plain text of HTTP without TLS. Any malicious actor with access to monitor user traffic may have been able to compromise account security. This issue has been addressed in in user_oidc v1.2.1. Users are advised to upgrade. Users unable to upgrade may use https to access Nextcloud. Set an HTTPS discovery URL in the provider settings (in Nextcloud OIDC admin settings).

Exploit Prediction Scoring System (EPSS)

The EPSS score estimates the probability that this vulnerability will be exploited in the near future.

EPSS Score: 0.06% (probability of exploit)

EPSS Percentile: 28.53% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 71.47% of others.

CVE-2022-39339 References

External References

• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-2vff-cq8h-chhg
• https://github.com/nextcloud/user_oidc/pull/495
• https://hackerone.com/reports/1687005
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-2vff-cq8h-chhg
• https://github.com/nextcloud/user_oidc/pull/495
• https://hackerone.com/reports/1687005

CWE Common Weakness Enumeration

CAPEC Common Attack Pattern Enumeration and Classification

• Session Sidejacking CAPEC-102 Session sidejacking takes advantage of an unencrypted communication channel between a victim and target system. The attacker sniffs traffic on a network looking for session tokens in unencrypted traffic. Once a session token is captured, the attacker performs malicious actions by using the stolen token with the targeted application to impersonate the victim. This attack is a specific method of session hijacking, which is exploiting a valid session token to gain unauthorized access to a target system or information. Other methods to perform a session hijacking are session fixation, cross-site scripting, or compromising a user or server machine and stealing the session token.
• Interception CAPEC-117 An adversary monitors data streams to or from the target for information gathering purposes. This attack may be undertaken to solely gather sensitive information or to support a further attack against the target. This attack pattern can involve sniffing network traffic as well as other types of data streams (e.g. radio). The adversary can attempt to initiate the establishment of a data stream or passively observe the communications as they unfold. In all variants of this attack, the adversary is not the intended recipient of the data stream. In contrast to other means of gathering information (e.g., targeting data leaks), the adversary must actively position themself so as to observe explicit data channels (e.g. network traffic) and read the content. However, this attack differs from a Adversary-In-the-Middle (CAPEC-94) attack, as the adversary does not alter the content of the communications nor forward data to the intended recipient.
• Harvesting Information via API Event Monitoring CAPEC-383 An adversary hosts an event within an application framework and then monitors the data exchanged during the course of the event for the purpose of harvesting any important data leaked during the transactions. One example could be harvesting lists of usernames or userIDs for the purpose of sending spam messages to those users. One example of this type of attack involves the adversary creating an event within the sub-application. Assume the adversary hosts a "virtual sale" of rare items. As other users enter the event, the attacker records via AiTM (CAPEC-94) proxy the user_ids and usernames of everyone who attends. The adversary would then be able to spam those users within the application using an automated script.
• Signature Spoofing by Mixing Signed and Unsigned Content CAPEC-477 An attacker exploits the underlying complexity of a data structure that allows for both signed and unsigned content, to cause unsigned data to be processed as though it were signed data.
• Sniff Application Code CAPEC-65 An adversary passively sniffs network communications and captures application code bound for an authorized client. Once obtained, they can use it as-is, or through reverse-engineering glean sensitive information or exploit the trust relationship between the client and server. Such code may belong to a dynamic update to the client, a patch being applied to a client component or any such interaction where the client is authorized to communicate with the server.

Other 5 Recently Published CVEs Vulnerabilities

• CVE-2025-3800 – A vulnerability has been found in WCMS 11 and classified as critical. Affected by this vulnerability is an unknown functionality of the file app/co...
• CVE-2025-3799 – A vulnerability, which was classified as critical, was found in WCMS 11. Affected is an unknown function of the file app/controllers/AnonymousContr...
• CVE-2025-3798 – A vulnerability, which was classified as critical, has been found in WCMS 11. This issue affects the function sub of the file app/admin/AdvadminCon...
• CVE-2025-3661 – The SB Chart block plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘className’ parameter in all versions up to, and inclu...
• CVE-2025-3404 – The Download Manager plugin for WordPress is vulnerable to arbitrary file deletion due to insufficient file path validation in the savePackage func...