XSS in Discourse

CVE-2026-53962

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, insufficient SVG sanitization in upload and user avatar handling could lead to cross-site scripting when a user visited specific URLs tha…

Vulnerability class: XSS (Cross-Site Scripting)

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

  • Discourse — versions >= 2026.1.0-latest, < 2026.1.5, >= 2026.4.0-latest, < 2026.4.2, >= 2026.5.0-latest, < 2026.5.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-53962?
CVE-2026-53962 is a medium-severity vulnerability in Discourse, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-07-09.
How severe is CVE-2026-53962?
Medium severity. CVSS v3 base score is 5.4 out of 10.