CVE-2026-7387CWE-863

Mattermost group syncable endpoints allow privilege escalation via scheme_admin

High · published June 12, 2026

CVSS v3.1
8.8
EPSS
0%
Percentile
34.9
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 Mattermost fails to require role-management authorization when setting the scheme_admin flag on group syncable link and patch endpoints, which allows a user with group-link permissions to escalate themselves and group members to team or channel admin via crafted API requests.. Mattermost Advisory ID: MMSA-2026-00665

The record
Technical detail
CVSS v3.1
8.8 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00417 · 34.9th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-06-12T15:54Z
EPSS history
Timeline
  • 12 JUN 15:54Z
    Mattermost group syncable endpoints allow privilege escalation via scheme_admin
    cvelistv5