CVE-2025-12756: Mattermost fails to validate user permissions when deleting comments in Boards

December 1, 2025 (updated December 2, 2025)

Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to validate user permissions when deleting comments in Boards, which allows an authenticated user with the editor role to delete comments created by other users.

References

github.com/advisories/GHSA-p6gj-jc38-x2m7
github.com/mattermost/mattermost
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2025-12756

Code Behaviors & Features

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