CVE-2026-55424
Description
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://github.com/discourse/discourse/commit/1bce8881e4253d9bbab56f011a12ef899b926b59
- https://github.com/discourse/discourse/commit/6679d9a5083488bae10c2adbb345c481c583242c
- https://github.com/discourse/discourse/commit/6828aee9b15c2655d63b515ac919830bd540ff83
- https://github.com/discourse/discourse/commit/c9b9405f5bd0bf0269e505e28e3aad388d7657c5
- https://github.com/discourse/discourse/releases/tag/v2026.1.5
- https://github.com/discourse/discourse/releases/tag/v2026.4.2
- https://github.com/discourse/discourse/releases/tag/v2026.5.1
- https://github.com/discourse/discourse/releases/tag/v2026.6.0
- https://github.com/discourse/discourse/security/advisories/GHSA-695w-7fv8-mxg3
CWEs
CWE-79
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.