CVE-2026-55424

Summary

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, a topic "featured link" was not sufficiently normalized and escaped before being rendered in the topic list, allowing a user who can set a featured link to inject JavaScript when default Content Security Policy protections were modified or disabled. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

Affected Software

VendorProductVersion RangeStatus
discoursediscourse>= 2026.1.0-latest, < 2026.1.5affected
discoursediscourse>= 2026.4.0-latest, < 2026.4.2affected
discoursediscourse>= 2026.5.0-latest, < 2026.5.1affected

Weaknesses

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

References