CVE-2026-82920 — Mattermost ABAC parent policy bypass via policy update endpoint

CVE-2026-82920

Mattermost ABAC parent policy bypass via policy update endpoint PUBLISHED

Description (CNA)

Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7 fail to enforce authorization boundaries on the access control policy update endpoint which allows a channel or team administrator to detach a system-assigned ABAC parent policy via a crafted PUT /api/v4/access_control_policies request with an empty imports list.. Mattermost Advisory ID: MMSA-2026-00724

Affected (CNA)

Vendor / product	Versions
Mattermost / Mattermost	affected 11.9.0 through 11.9.0; affected 11.8.0 through 11.8.4; affected 11.7.0 through 11.7.7; unaffected 11.10.0; unaffected 11.9.1; unaffected 11.8.5; unaffected 11.7.8

CWE

CWE-863

References

https://mattermost.com/security-updates

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.