Vulnerability · Published Mar 19, 2026 · Assigned by GitHub_M

CVE-2026-33395Discourse has stored click‑based XSS via Graphviz SVG javascript: links

Medium 4.4

In plain English

A medium-severity cross-site scripting in discourse from discourse. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).

Severity (CVSS 3.1)4.4Medium

Exploit odds (30 days)0.2%top 86.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
discourse	discourse	>= 2026.1.0-latest, < 2026.1.2>= 2026.2.0-latest, < 2026.2.1= 2026.3.0-latest

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/discourse/discourse/security/advisories/GHSA-23c7-gq89-xm5v x_refsource_CONFIRM
https://github.com/discourse/discourse/commit/0471e68ed0b594bf386e068f228849244b880ef1 x_refsource_MISC
https://github.com/discourse/discourse/commit/0c861df8bea03dcc01b60da6cc7038e6c88de4ee x_refsource_MISC
https://github.com/discourse/discourse/commit/472f9e1f7855307e489e9eaa6825d5335dfc08b5 x_refsource_MISC