CVEvulnerability
CVE-2026-9859
6.5 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-08-17
- Last modified
- 2026-08-19
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 6.5 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- Weaknesses
- CWE-863
Description
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fail to enforce PermissionManageBoardRoles on the channelId field of the batch endpoint, which allows an authenticated board editor to relink any board they can edit to an arbitrary channel via a crafted PATCH request. Mattermost Advisory ID: MMSA-2026-00686
Affected configurations
• mattermost mattermost server (>= 10.11.0 < 10.11.22)
• mattermost mattermost server (>= 11.7.0 < 11.7.7)
• mattermost mattermost server (>= 11.8.0 < 11.8.4)
Related
Weakness · CWE (1)
- CWE-863 Incorrect Authorization weakness
References
- https://mattermost.com/security-updates Vendor Advisory