CVE-2026-33395 MEDIUM

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

Vendor Discourse
Product discourse
Weakness CWE-79 · XSS
Published March 19, 2026
Last update March 20, 2026

CVSS base score

4.4/10
Attack vector Network
Attack complexity High
Privileges required Low
User interaction Required
Confidentiality Low
Integrity Low

CVSS vector

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

What the vulnerability does

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.

Key dates

Disclosure timeline

March 19, 2026 CVE published
March 20, 2026 Record updated