CVE-2025-62690: Mattermost Server

Medium severity, CVSS 6.1. EPSS: 0.1% chance of exploitation in the next 30 days.

Mattermost versions 10.11.x <= 10.11.4 fail to validate redirect URLs on the /error page, which allows an attacker to redirect a victim to a malicious site via a crafted link opened in a new tab.

Affected products

• Mattermost Mattermost Server: from 10.11.0, before 10.11.5 (fixed in 10.11.5)

Published 2025-12-17. Last modified 2026-06-17.