Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to enforce access permissions on the Agents plugin which allows other users to determine when users had read channels via channel member objects
https://mattermost.com/security-updates
Source: Mitre, NVD
Published: 2025-11-18
Updated: 2025-11-25
Base Score: 4
Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N
Severity: Medium
Base Score: 3.5
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
Severity: Low
EPSS: 0.00024