CVE-2024-23488: Mattermost Server

Medium severity, CVSS 4.3. EPSS: 0.3% chance of exploitation in the next 30 days.

Mattermost fails to properly restrict the access of files attached to posts in an archived channel, resulting in members being able to access files of archived channels even if the “Allow users to view archived channels” option is disabled.

Affected products

• Mattermost Mattermost Server: before 8.1.9 (fixed in 8.1.9); from 9.0.0, before 9.4.2 (fixed in 9.4.2)

Published 2024-02-29. Last modified 2026-06-17.