CVE-2026-72722
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account. Limited direct impact.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 4.3 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-862 · Missing authorization
- Record status
- Deferred
Attack profile CVSS 3.1 · 4.3
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-72722.md and follow it. Check whether this project is affected by CVE-2026-72722. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- 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
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