CVE-2023-37465: 
Java Análise e mitigação de vulnerabilidades

CVE-2023-37465 is a Cross-Site Request Forgery (CSRF) vulnerability in the XWiki Discussion Extension (org.xwiki.contrib:discussions-server) that allows an attacker to forge requests to delete discussion messages. It affects all versions prior to 2.0-rc-1 (specifically versions below 1.1 per the repository advisory). The vulnerability was published on July 23, 2026, and carries a CVSS v3.1 base score of 6.5 (Medium) (GitHub Advisory, XWiki Advisory).

The root cause is classified as CWE-352 (Cross-Site Request Forgery), meaning the discussions-server component does not sufficiently verify that incoming requests to delete messages were intentionally initiated by the authenticated user. An attacker can craft a malicious web page or link that, when visited by an authenticated XWiki user, silently sends a forged delete-message request to the vulnerable endpoint on the target XWiki instance. No privileges are required on the attacker's side, but user interaction (victim visiting a malicious page) is necessary. The specific vulnerable endpoint and request format are referenced in the upstream Jira issue DISCUSSION-22 (GitHub Advisory).

Successful exploitation allows an unauthenticated attacker to permanently delete discussion messages on behalf of an authenticated victim, resulting in a high integrity impact with no confidentiality or availability impact. This could be used to disrupt collaborative workflows, erase important discussion content, or perform targeted content destruction on XWiki instances using the Discussion Extension (GitHub Advisory, XWiki Advisory).

1. Reconnaissance: Identify a target XWiki instance running the Discussion Extension (org.xwiki.contrib:discussions-server) at a version below 2.0-rc-1.
2. Identify target endpoint: Determine the HTTP endpoint used to delete discussion messages (referenced in DISCUSSION-22 on Jira XWiki), typically a GET or POST request to a discussions-related action URL.
3. Craft malicious payload: Create an HTML page or image tag that automatically sends a forged HTTP request to the delete-message endpoint, including any required message identifier parameters.
4. Deliver to victim: Trick an authenticated XWiki user into visiting the malicious page (e.g., via phishing email or embedding in another web page).
5. Message deletion: The victim's browser sends the forged request with their session credentials, causing the target message to be deleted without their knowledge (GitHub Advisory).

• Logs: Unexpected DELETE or POST requests to discussion message endpoints in XWiki access logs, originating from authenticated user sessions but with unusual referrer headers (e.g., external or blank referrer).
• Application: Unexplained disappearance of discussion messages, particularly if reported by users who did not intentionally delete them.
• Network: HTTP requests to XWiki discussion endpoints with Referer headers pointing to external or unknown domains.

The vulnerability has been patched in version 2.0-rc-1 of the XWiki Discussion Extension (org.xwiki.contrib:discussions-server). There is no documented workaround other than upgrading to the patched version. Administrators should update the Discussion Extension to 2.0-rc-1 or later as soon as possible (GitHub Advisory, XWiki Advisory).