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
- Versión: 4.0
- 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 6.9
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.34%
- Percentil entre todas las CVEs puntuadas: 25
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-862
Referencias
- https://github.com/discourse/discourse/commit/60a588f4da4ab0feceb2c44787d4261b4f8757be
- https://github.com/discourse/discourse/commit/d3cb203feabc46d765ecb91f348613a2bd531b89
- https://github.com/discourse/discourse/commit/f5fef73827da7520efc517357bd2a6bab35d7886
- https://github.com/discourse/discourse/security/advisories/GHSA-xq37-5fvf-4m4j
JSON original (NVD)
Mostrar
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