GHSA-m2w9-h2mm-79qrMediumCVSS 6.7

Mattermost doesn't require system-level permission when patching protected default system roles

Published
June 12, 2026
Last Modified
August 24, 2026

🔗 CVE IDs covered (1)

📋 Description

Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to require system-level permission when patching protected default system roles, which allows authenticated users with delegated user-management permissions to escalate privileges by altering built-in role permissions via the role patch API. Mattermost Advisory ID: MMSA-2026-00656

🎯 Affected products4

  • go/github.com/mattermost/mattermost-server:= 11.6.0
  • go/github.com/mattermost/mattermost-server:>= 11.5.0, <= 11.5.4
  • go/github.com/mattermost/mattermost-server:>= 10.11.0, <= 10.11.15
  • go/github.com/mattermost/mattermost/server/v8:>= 8.0.0-20250731163400-5b955468ea1e, < 8.0.0-20260501142004-99b73d4c4acf

🔗 References (16)