PT-2026-57001 · Discourse · Discourse

Published 2026-07-09 · Updated 2026-07-09 · CVE-2026-55424

Mitre

CVSS v4.0

7.4

High

Base vector

AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

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.

Fix

XSS

Weakness Enumeration

CWE-79

Related Identifiers

CVE-2026-55424

Affected Products

Discourse

References · 10

• https://nvd.nist.gov/vuln/detail/CVE-2026-55424 · Security Note
• https://github.com/discourse/discourse/releases/tag/v2026.6.0 · Note
• https://github.com/discourse/discourse/releases/tag/v2026.5.1 · Note
• https://github.com/discourse/discourse/commit/c9b9405f5bd0bf0269e505e28e3aad388d7657c5 · Note
• https://github.com/discourse/discourse/security/advisories/GHSA-695w-7fv8-mxg3 · Note
• https://github.com/discourse/discourse/commit/6828aee9b15c2655d63b515ac919830bd540ff83 · Note
• https://github.com/discourse/discourse/commit/1bce8881e4253d9bbab56f011a12ef899b926b59 · Note
• https://github.com/discourse/discourse/commit/6679d9a5083488bae10c2adbb345c481c583242c · Note
• https://github.com/discourse/discourse/releases/tag/v2026.1.5 · Note
• https://github.com/discourse/discourse/releases/tag/v2026.4.2 · Note