CVE-2026-9820

Summary

Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671

Affected Software

VendorProductVersion RangeStatus
MattermostMattermost11.7.0 <= 11.7.2affected
MattermostMattermost10.11.0 <= 10.11.19affected
MattermostMattermost11.8.0unaffected
MattermostMattermost11.7.3unaffected
MattermostMattermost10.11.20unaffected

Weaknesses

  • CWE-862: CWE-862: Missing Authorization

ADP Enrichment

CISA ADP Vulnrichment

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

References