Vulnerability · Published Mar 19, 2026 · Assigned by GitHub_M

CVE-2026-27491Discourse has a bypass of official warnings messages by non-staff users

Medium 6.9

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 28% of all known vulnerabilities).

Severity (CVSS 4.0)6.9Medium

Exploit odds (30 days)0.3%top 71.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
discourse	discourse	>= 2026.1.0-latest, < 2026.1.2>= 2026.2.0-latest, < 2026.2.1= 2026.3.0-latest

Weakness: CWE-862 · Vector: 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

References

https://github.com/discourse/discourse/security/advisories/GHSA-xq37-5fvf-4m4j x_refsource_CONFIRM
https://github.com/discourse/discourse/commit/60a588f4da4ab0feceb2c44787d4261b4f8757be x_refsource_MISC
https://github.com/discourse/discourse/commit/d3cb203feabc46d765ecb91f348613a2bd531b89 x_refsource_MISC
https://github.com/discourse/discourse/commit/f5fef73827da7520efc517357bd2a6bab35d7886 x_refsource_MISC