SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-33411

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.

MEDIUM 5.4EPSS 0.20%

Does this matter?

Lower severity and a low EPSS score (0.20%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1
5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS
0.20% probability · 10th percentile
CISA KEV
Not listed
Weakness
CWE-79
Affected
discourse/discourse
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.