CVE-2026-4055

Summary

Mattermost versions 11.5.x <= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629

Affected Software

VendorProductVersion RangeStatus
MattermostMattermost11.5.0 <= 11.5.1affected
MattermostMattermost11.6.0unaffected
MattermostMattermost11.5.2unaffected
MattermostMattermost10.11.14unaffected
MattermostMattermost11.4.4unaffected

Weaknesses

  • CWE-863: CWE-863: Incorrect Authorization

ADP Enrichment

CISA ADP Vulnrichment

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

References