CVE-2026-33411: Discourse

Medium severity, CVSS 5.4. EPSS: 0.3% chance of exploitation in the next 30 days.

Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a potential stored XSS in topic titles for the solved posts stream. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.

Affected products

• Discourse Discourse: from 2026.1.0, before 2026.1.2 (fixed in 2026.1.2); from 2026.2.0, before 2026.2.1 (fixed in 2026.2.1); version 2026.3.0 only

Published 2026-03-20. Last modified 2026-06-17.