CVE-2026-6739CWE-863

Mattermost: Delegated admins could patch protected default system roles

Medium · published June 12, 2026

CVSS v3.1
6.7
EPSS
0%
Percentile
39.0
In the wild
Unconfirmed
What it is

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

The record
Technical detail
CVSS v3.1
6.7 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L
CVSS v4.0
Not supplied
EPSS
0.00462 · 39.0th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-06-12T15:49Z
EPSS history
Timeline
  • 12 JUN 15:49Z
    Mattermost: Delegated admins could patch protected default system roles
    cvelistv5