CVE-2026-33395

Summary

Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the discourse-graphviz plugin contains a stored cross-site scripting (XSS) vulnerability that allows authenticated users to inject malicious JavaScript code through DOT graph definitions. For instances with CSP disabled only. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, disable the graphviz plugin, upgrade to a patched version, or enable a content security policy.

Impact & exploitability

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

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://github.com/discourse/discourse/commit/0471e68ed0b594bf386e068f228849244b880ef1 ↗

Additional information

• NVD record
• https://github.com/discourse/discourse/commit/0471e68ed0b594bf386e068f228849244b880ef1Patch
• https://github.com/discourse/discourse/commit/0c861df8bea03dcc01b60da6cc7038e6c88de4eePatch
• https://github.com/discourse/discourse/commit/472f9e1f7855307e489e9eaa6825d5335dfc08b5Patch
• https://github.com/discourse/discourse/security/advisories/GHSA-23c7-gq89-xm5vAdvisory