Medium severity · published Aug 17, 2026
CVE-2026-59829
Discourse: Review queue exposes flag-related private message excerpts to category group moderators
4.3
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DI
discourse · discourse
>= 2026.1.0-latest, < 2026.1.6; >= 2026.5.0-latest, < 2026.5.2; < 2026.6.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59829
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-59829
github.com
https://github.com/discourse/discourse/commit/4df0e54f59361c78606b578ad12a2c39b4dd9f59
github.com
https://github.com/discourse/discourse/commit/58e45dc7c92d19d5294c73fbcd3833c73dc51754
github.com
https://github.com/discourse/discourse/commit/74c8522a197658c69b0adefa182f601ce85dcefa
github.com
https://github.com/discourse/discourse/commit/e56bd3ec58ae387946220821d1ce214eed02d1b9
github.com
https://github.com/discourse/discourse/pull/41527
github.com
https://github.com/discourse/discourse/security/advisories/GHSA-wmc6-pmxp-xw5w
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