CVE-2026-7387
Mattermost group syncable endpoints allow privilege escalation via scheme_admin
CVSS Score
8.8
EPSS Score
0.0%
EPSS Percentile
0th
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
| CWE | CWE-863 |
| Vendor | mattermost |
| Product | mattermost |
| Published | Jun 12, 2026 |
| Last Updated | Jun 12, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
Mattermost / Mattermost
11.6.0 ≤ 11.6.1 11.5.0 ≤ 11.5.4 10.11.0 ≤ 10.11.15 10.11.0 ≤ 10.11.16
Credits
winfunc