cbcvebase.
CVE-2026-7387
published 2026-06-12

CVE-2026-7387: 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…

PriorityP355high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EPSS
0.31%
23.4th percentile
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

Affected

7 ranges
VendorProductVersion rangeFixed in
github.commattermost_mattermost-server>= 10.11.0 < 10.11.1710.11.17
github.commattermost_mattermost-server>= 11.5.0 < 11.5.511.5.5
github.commattermost_mattermost-server>= 11.6.0 < 11.6.111.6.1
github.commattermost_mattermost_server_v8>= 8.0.0-20250731163400-5b955468ea1e < 8.0.0-20260506065351-202d125afa878.0.0-20260506065351-202d125afa87
mattermostmattermost10.11.0 – 10.11.15
mattermostmattermost11.5.0 – 11.5.4
mattermostmattermost11.6.0 – 11.6.1
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