CVE-2026-21865

medium

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.

References

https://github.com/discourse/discourse/security/advisories/GHSA-4777-wrv5-3g39

Details

Source: Mitre, NVD

Published: 2026-01-28

Updated: 2026-01-28

Risk Information

CVSS v2

Base Score: 7.7

Vector: CVSS2#AV:N/AC:L/Au:M/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

Severity: Medium