Vulnerability · Published Mar 20, 2026 · Assigned by GitHub_M

CVE-2026-33411Discourse's solved topic stream has potential stored XSS in topic title

Medium 5.4

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 11% of all known vulnerabilities).

Severity (CVSS 3.1)5.4Medium

Exploit odds (30 days)0.2%top 88.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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 (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:L/PR:L/UI:N/S:U/C:L/I:L/A:N

References

https://github.com/discourse/discourse/security/advisories/GHSA-j3mm-ghh2-83x2 x_refsource_CONFIRM