Mattermost Server 9.11.x < 9.11.18 / 10.5.x < 10.5.9 / 10.8.x < 10.8.4 / 10.9.x < 10.9.3 / 10.10.x < 10.10.1 / 10.11.0 Unrestricted Upload of File (MMSA-2025-00505)

The version of Mattermost Server installed on the remote host is affected by a vulnerability as referenced in the MMSA-2025-00505 advisory. - Mattermost versions 10.8.x = 10.8.3, 10.5.x = 10.5.8, 9.11.x = 9.11.17, 10.9.x = 10.9.2, 10.10.x = 10.10.0 fail to validate upload types in remote cluster...

CVE-2025-49222

Mattermost CVE-2025-49222 affects Mattermost Server versions 9.11.x, 10.5.x, 10.8.x, 10.9.x, and 10.10.x, where upload type validation in remote cluster upload sessions can be bypassed, allowing a system admin to upload non‑attachment file types that may be placed in arbitrary filesystem director...