CVE-2026-72724
Discourse: Private Chat Threat Message Disclosure via Chat Onebox Channel/Threat ID Mismatch
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Timeline
ID reserved
By GitHub_M
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
| NVDNVD · Deferred | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.63% · top 50% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Weakness
Affected products
References (9)
- https://github.com/discourse/discourse/security/advisories/GHSA-8g98-fvfc-9w48 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/discourse/discourse/pull/42091 (opens in a new tab)x_refsource_MISC
- https://github.com/discourse/discourse/pull/42092 (opens in a new tab)x_refsource_MISC
- https://github.com/discourse/discourse/pull/42093 (opens in a new tab)x_refsource_MISC
- https://github.com/discourse/discourse/pull/42094 (opens in a new tab)x_refsource_MISC
- https://github.com/discourse/discourse/commit/1276d7032af8803956c74ae87ccfd976938dcd75 (opens in a new tab)x_refsource_MISC
- https://github.com/discourse/discourse/commit/45ab6d54076de9ca4965888974d4416d5b48e83c (opens in a new tab)x_refsource_MISC
- https://github.com/discourse/discourse/commit/49efe1d7f098f2ce7301908815a211cc9248270f (opens in a new tab)x_refsource_MISC
- https://github.com/discourse/discourse/commit/dc54846f0754799591717b6018343e49524e41ce (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-72724)Record last updated .