CVE-2026-6739

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-i...

CVE-2026-6739 Mattermost: Delegated admins could patch protected default system roles

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-i...

EUVD-2026-36499

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-i...

CVE-2026-6739

Mattermost vulnerability CVE-2026-6739 affects multiple releases: 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, and 10.11.x

PT-2026-48938

Name of the Vulnerable Software and Affected Versions Mattermost versions prior to 11.6.2 Mattermost versions prior to 11.5.5 Mattermost versions prior to 10.11.17 Description Authenticated users with delegated user-management permissions can escalate privileges by altering built-in role...