CVE-2026-27491
Discourse has a bypass of official warnings messages by non-staff users
- State
- Published
- Severity
- 6.9 Medium
- Published
- Mar 19, 2026
- Updated
- Mar 20, 2026
- Reserved
- Feb 19, 2026
Description
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, a type coercion issue in a post actions API endpoint allowed non-staff users to issue warnings to other users. Warnings are a staff-only moderation feature. The vulnerability required the attacker to be a logged-in user and to send a specifically crafted request. No data exposure or privilege escalation beyond the ability to create unauthorized user warnings was possible. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.9 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-862 Missing Authorization
Affected Products
| Product | Versions |
|---|---|
discoursediscourse |
|
References
- https://github.com/discourse/discourse/security/advisories/GHSA-xq37-5fvf-4m4j
- https://github.com/discourse/discourse/commit/60a588f4da4ab0feceb2c44787d4261b4f8757be
- https://github.com/discourse/discourse/commit/d3cb203feabc46d765ecb91f348613a2bd531b89
- https://github.com/discourse/discourse/commit/f5fef73827da7520efc517357bd2a6bab35d7886
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.