CVE-2026-72722
Discourse is an open-source discussion platform.
Does this matter?
Lower severity and a low EPSS score (0.32%). Track it; it rarely justifies an emergency change on its own.
Description
Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, TopicLink.extract_from, TopicLink.ensure_entry_for, and TopicLink.duplicate_lookup do not consistently enforce Guardian.can_see? checks when processing internal links. An authenticated user can submit links to restricted topics, private messages, or hidden posts and receive canonicalized slugs or titles in the composer_messages duplicate_lookup response even though the targets are not visible to that user. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.
- CVSS 3.1
- 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
- EPSS
- 0.32% probability · 25th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-862
- Source
- security-advisories@github.com
References
- https://github.com/discourse/discourse/commit/45abd925e46e8be40d2d047bced26628f26e4e31
- https://github.com/discourse/discourse/commit/7d7ce546ac86e24a6512b321ace69fc52fe37bf4
- https://github.com/discourse/discourse/commit/836a251d54a1004fb1c463a7d299b933b176191f
- https://github.com/discourse/discourse/commit/e54ba27eacee0f14f315e510e287e7ac2e4bdb1a
- https://github.com/discourse/discourse/pull/42091
- https://github.com/discourse/discourse/pull/42092
- https://github.com/discourse/discourse/pull/42093
- https://github.com/discourse/discourse/pull/42094
- https://github.com/discourse/discourse/security/advisories/GHSA-4fx9-5m29-83p4
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.