CVE-2026-9812

Mattermost versions 11.9.x ≤ 11.9.0, 11.8.x ≤ 11.8.4, 11.7.x ≤ 11.7.7, and 10.11.x ≤ 10.11.22 contain a missing validation flaw in the Playbooks plugin's run property update endpoint. The endpoint does not verify that a referenced property field belongs to the specified run before updating its va...

PT-2026-91162

Mattermost versions 11.9.x = 11.9.0, 11.8.x = 11.8.4, 11.7.x = 11.7.7, 10.11.x = 10.11.22 fail to validate that a property field belongs to the specified run before updating its value which allows an authenticated user with run property-management access to crash the Playbooks plugin via a REST...