Vulnerability · Published Jan 28, 2026 · Assigned by GitHub_M
CVE-2026-21865Discourse topic conversion permission vulnerability for moderators
Medium 6.5
In plain English
A medium-severity missing authorization in discourse from discourse. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities).
Official description
Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, moderators can convert some personal messages to public topics when they shouldn't have access. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a workaround, site admin can temporarily revoke the moderation role from untrusted moderators or remove the moderator group from the "personal message enabled groups" site setting until the Discourse instance has been upgraded to a version that has been patched.
Affected products (as reported)
Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
References
- https://github.com/discourse/discourse/security/advisories/GHSA-4777-wrv5-3g39 x_refsource_CONFIRM