CVE-2026-16044

Summary

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which allows a board member to escalate a guest user to Board Admin via importing a crafted .boardarchive file. Mattermost Advisory ID: MMSA-2026-00672

Affected Software

VendorProductVersion RangeStatus
MattermostMattermost11.7.0 <= 11.7.6affected
MattermostMattermost10.11.0 <= 10.11.21affected
MattermostMattermost11.9.0unaffected
MattermostMattermost11.7.7unaffected
MattermostMattermost10.11.22unaffected

Weaknesses

  • CWE-863: CWE-863: Incorrect Authorization

ADP Enrichment

CISA ADP Vulnrichment

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

References