XSS in Discourse
CVE-2026-27570
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the onebox method in the SharedAiConversation model renders the conversation title directly into HTML without proper sanitization…
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.000 (5.0th percentile) — read the EPSS interpretation.
Affected products
- Discourse — versions >= 2026.1.0-latest, < 2026.1.2, >= 2026.2.0-latest, < 2026.2.1, = 2026.3.0-latest
Weakness classification (CWE)
References
- https://github.com/discourse/discourse/security/advisories/GHSA-hfxw-89hw-vwmv (x_refsource_CONFIRM)
- https://github.com/discourse/discourse/commit/43a5a60b595f0120e6adfc131f2408508fe341f1 (x_refsource_MISC)
- https://github.com/discourse/discourse/commit/c14f8f52b7999328bd9f8665f2ecfa24dadc4bf1 (x_refsource_MISC)
- https://github.com/discourse/discourse/commit/f2aafa5c7467c94fcd4ebd36785a98e77ca088cc (x_refsource_MISC)