CVE-2026-59830

Published: Sep 21, 2026Modified: Sep 23, 2026Deferred

5.4

Vector

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

Exploitability: 2.3 / Impact: 2.7

Source: security-advisories@github.com (Secondary)

Description

Discourse is an open-source discussion platform. Prior to 2026.7.0, the post action component failed to escape user-controlled display names before interpolating them into an HTML string passed to trustHTML. A user who could choose a crafted display name could persist markup in post action descriptions. Viewing the affected user activity streams could execute attacker-controlled script in another user's browser. This issue is fixed in version 2026.7.0.

Related CWEs

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

References (3)

https://github.com/discourse/discourse/commit/dd786594ddd088657a7e6f9fefba5bd889965fe4

Source: security-advisories@github.com

https://github.com/discourse/discourse/releases/tag/v2026.7.0

Source: security-advisories@github.com

https://github.com/discourse/discourse/security/advisories/GHSA-x6mf-p7cg-69rw

Source: security-advisories@github.com

Timeline

No history available yet.