GHSA-pp9j-pf5c-659xMediumCVSS 5.7

Mattermost fails to sanitize sensitive data in WebSocket messages

Published
February 16, 2026
Last Modified
February 19, 2026

🔗 CVE IDs covered (1)

CVE-2025-13821 →

📋 Description

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to sanitize sensitive data in WebSocket messages which allows authenticated users to exfiltrate password hashes and MFA secrets via profile nickname updates or email verification events. Mattermost Advisory ID: MMSA-2025-00560

🎯 Affected products5

  • go/github.com/mattermost/mattermost/server/v8:< 8.0.0-20251210191531-cd17b61de41b
  • go/github.com/mattermost/mattermost-server:>= 11.1.0, < 11.1.3
  • go/github.com/mattermost/mattermost-server:>= 10.11.0, < 10.11.10
  • go/github.com/mattermost/mattermost-server:>= 11.2.0, < 11.2.2
  • go/github.com/mattermost/mattermost-server:< 5.3.2-0.20251210191531-cd17b61de41b

🔗 References (4)