CVE-2026-59829 Discourse: Review queue exposes flag-related private message excerpts to category group moderators
Category group moderators can view unauthorized private message excerpts in the review queue on Discourse sites with category group moderation enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-59829?
CVE-2026-59829 is a medium-severity missing authorization vulnerability in discourse, published on 17 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.1, on sites with category group moderation enabled, the review queue could include an excerpt (and permalink) of the private message attached to a flag, even when the reviewing category moderator was not a participant in that message. These notify_moderators flag messages are addressed only to moderators and, for core flags, to a category's moderation groups as they existed when the flag was raised, so a category group moderator could read flag-discussion content they were not authorized to see. This affects official plugins that create such messages and core flags raised before a moderator's group was granted moderation of the category. Only the confidentiality of a limited excerpt of these flag-related private messages is affected; no content can be modified or deleted. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.1.
Weakness: CWE-862
Which versions are affected by CVE-2026-59829?
1 open source package ship an affected version, including discourse.
| Package | Affected | Fixed in |
|---|---|---|
discourse Bitnami | All versions | 2026.6.1 |
How do I fix CVE-2026-59829?
Upgrade discourse to 2026.6.1 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-59829 being exploited?
There is no known exploitation of CVE-2026-59829 in the wild and no public exploit code.
Sources
Also known as BIT-discourse-2026-59829, GHSA-wmc6-pmxp-xw5w.