CVE-2024-4182: Mattermost Server

Medium severity, CVSS 4.3. EPSS: 0.6% chance of exploitation in the next 30 days.

Mattermost versions 9.6.0, 9.5.x before 9.5.3, 9.4.x before 9.4.5, and 8.1.x before 8.1.12 fail to handle JSON parsing errors in custom status values, which allows an authenticated attacker to crash other users' web clients via a malformed custom status.

Affected products

• Mattermost Mattermost Server: from 8.1.0, before 8.1.12 (fixed in 8.1.12); from 9.4.0, before 9.4.5 (fixed in 9.4.5); from 9.5.0, before 9.5.3 (fixed in 9.5.3); from 9.6.0, before 9.6.1 (fixed in 9.6.1)

Published 2024-04-26. Last modified 2026-06-17.