CVE-2026-82920

Summary

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 Software

VendorProductVersion RangeStatus
MattermostMattermost11.9.0 <= 11.9.0affected
MattermostMattermost11.8.0 <= 11.8.4affected
MattermostMattermost11.7.0 <= 11.7.7affected
MattermostMattermost11.10.0unaffected
MattermostMattermost11.9.1unaffected
MattermostMattermost11.8.5unaffected
MattermostMattermost11.7.8unaffected

Weaknesses

  • CWE-863: CWE-863: Incorrect Authorization

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References