CVE-2026-27769

Summary

Mattermost versions 10.11.x <= 10.11.12 fail to validate whether users were correctly owned by the correct Connected Workspace which allows a malicious remote server connected using the Conntexted Workspaces feature to change the displayed status of local users via the Connected Workspaces API.. Mattermost Advisory ID: MMSA-2026-00603

Affected Software

VendorProductVersion RangeStatus
MattermostMattermost10.11.0 <= 10.11.12affected
MattermostMattermost11.5.0unaffected
MattermostMattermost10.11.13unaffected

Weaknesses

  • CWE-862: CWE-862: Missing Authorization

ADP Enrichment

CISA ADP Vulnrichment

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

References