CVE-2026-27491

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.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/commit/60a588f4da4ab0feceb2c44787d4261b4f8757be	Patch
https://github.com/discourse/discourse/commit/d3cb203feabc46d765ecb91f348613a2bd531b89	Patch
https://github.com/discourse/discourse/commit/f5fef73827da7520efc517357bd2a6bab35d7886	Patch
https://github.com/discourse/discourse/security/advisories/GHSA-xq37-5fvf-4m4j	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.3.0::::latest:::

History

No history.

Information

Published : 2026-03-19 21:17

Updated : 2026-03-25 01:00

NVD link : CVE-2026-27491

Mitre link : CVE-2026-27491

CVE.ORG link : CVE-2026-27491

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-862

Missing Authorization

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La vulnerabilidad requer\u00eda que el atacante fuera un usuario con sesi\u00f3n iniciada y enviara una solicitud espec\u00edficamente dise\u00f1ada. No fue posible la exposici\u00f3n de datos ni la escalada de privilegios m\u00e1s all\u00e1 de la capacidad de crear advertencias de usuario no autorizadas. Las versiones 2026.3.0-latest.1, 2026.2.1 y 2026.1.2 contienen un parche. 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