Mattermost Server: Mehrere Schwachstellen ermöglichen die Umgehung von Sicherheitsmaßnahmen

Summary

Product

Vulnerabilities 2

• Critical 9.9
  CVE-2025-12419

  Account takeover on OAuth/OpenID-enabled servers

  Mattermost versions 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12, 11.0.x <= 11.0.3 fail to properly validate OAuth state tokens during OpenID Connect authentication which allows an authenticated attacker with team creation privileges to take over…

  Mattermost Mattermost github.com/mattermost/mattermost-server github.com/mattermost/mattermost-server/v6 Go
  Nov 27, 2025
• Critical 9.9
  CVE-2025-12421

  Account Takeover via Code Exchange Endpoint

  Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to to verify that the token used during the code exchange originates from the same authentication flow, which allows an authenticated user to perform account …

  Mattermost Mattermost github.com/mattermost/mattermost-server github.com/mattermost/mattermost-server/v6 Go
  Nov 27, 2025

Revision history

1. 2025-11-27 #2

   Neue Updates von Mattermost

2. 2025-10-28 #1

   Initiale Fassung

References

• Mattermost Security Updates vom 2025-10-28
  https://mattermost.com/security-updates/#server