CVE-2026-72724
Discourse is an open-source discussion platform.
Does this matter?
Lower severity and a low EPSS score (0.46%). 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, plugins/chat/lib/chat/onebox_handler.rb resolves Chat::Thread by route thread_id independently of the route channel_id before checking whether the user can preview the selected chat channel. An authenticated user can pair a public channel ID with a private thread ID in a /onebox.json request and obtain private thread message content. 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
- 0.46% probability · 39th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-639
- Source
- security-advisories@github.com
References
- https://github.com/discourse/discourse/commit/1276d7032af8803956c74ae87ccfd976938dcd75
- https://github.com/discourse/discourse/commit/45ab6d54076de9ca4965888974d4416d5b48e83c
- https://github.com/discourse/discourse/commit/49efe1d7f098f2ce7301908815a211cc9248270f
- https://github.com/discourse/discourse/commit/dc54846f0754799591717b6018343e49524e41ce
- 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-8g98-fvfc-9w48
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.