CVE-2026-27491

medium

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.

References

https://github.com/discourse/discourse/security/advisories/GHSA-xq37-5fvf-4m4j

https://github.com/discourse/discourse/commit/f5fef73827da7520efc517357bd2a6bab35d7886

https://github.com/discourse/discourse/commit/d3cb203feabc46d765ecb91f348613a2bd531b89

https://github.com/discourse/discourse/commit/60a588f4da4ab0feceb2c44787d4261b4f8757be

Details

Source: Mitre, NVD

Published: 2026-03-19

Updated: 2026-03-25

Risk Information

CVSS v2

Base Score: 4

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

Severity: Medium

CVSS v3

Base Score: 4.3

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

Severity: Medium

CVSS v4

Base Score: 6.9

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

Severity: Medium

EPSS

EPSS: 0.00039