CVE-2026-7387

Mattermost group syncable endpoints allow privilege escalation via scheme_admin

State: Published
Severity: 8.8 High
Published: Jun 12, 2026
Updated: Jun 13, 2026
Reserved: Apr 29, 2026

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 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

Scores

CVSS	Score	Vector	Source
3.1	8.8 High	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Mattermost

Weaknesses

CWE-863 Incorrect Authorization

Affected Products

Product	Versions
MattermostMattermost	11.6.0 through 11.6.1Affected 11.5.0 through 11.5.4Affected 10.11.0 through 10.11.15Affected 10.11.0 through 10.11.16Affected 11.7.0Not affected 11.6.2Not affected 11.5.5Not affected 10.11.16Not affected 10.11.17Not affected

References

MMSA-2026-00665vendor-advisory

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.