CVE-2024-41926: Mattermost Server

Medium severity, CVSS 4.3. EPSS: 0.2% chance of exploitation in the next 30 days.

Mattermost versions 9.9.x <= 9.9.0 and 9.5.x <= 9.5.6 fail to validate the source of sync messages and only allow the correct remote IDs, which allows a malicious remote to set arbitrary RemoteId values for synced users and therefore claim that a user was synced from another remote.

Affected products

• Mattermost Mattermost Server: from 9.5.0, before 9.5.7 (fixed in 9.5.7); version 9.9.0 only

Published 2024-08-01. Last modified 2026-06-17.