CVE-2026-33411

Summary

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 Software

VendorProductVersion RangeStatus
discoursediscourse>= 2026.1.0-latest, < 2026.1.2affected
discoursediscourse>= 2026.2.0-latest, < 2026.2.1affected
discoursediscourse= 2026.3.0-latestaffected

Weaknesses

  • CWE-79: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References