CVE-2026-33411

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/security/advisories/GHSA-j3mm-ghh2-83x2	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.3.0::::latest:::

History

24 Mar 2026, 21:11

Type	Values Removed	Values Added
First Time		Discourse Discourse discourse
CPE		cpe:2.3:a:discourse:discourse:2026.3.0::::latest::: cpe:2.3:a:discourse:discourse::::::::
References	~~() https://github.com/discourse/discourse/security/advisories/GHSA-j3mm-ghh2-83x2 -~~	() https://github.com/discourse/discourse/security/advisories/GHSA-j3mm-ghh2-83x2 - Mitigation, Vendor Advisory

20 Mar 2026, 23:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-20 23:16

Updated : 2026-03-24 21:11

NVD link : CVE-2026-33411

Mitre link : CVE-2026-33411

CVE.ORG link : CVE-2026-33411

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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