CVE-2026-6961

Summary

Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to sanitize FileInfo.Name received from federated peers during shared channel file sync, which allows an attacker who controls a federated server to write files to arbitrary locations within the target server's filestore via path traversal sequences in the filename field.. Mattermost Advisory ID: MMSA-2026-00661

Affected Software

VendorProductVersion RangeStatus
MattermostMattermost11.6.0 <= 11.6.1affected
MattermostMattermost11.5.0 <= 11.5.4affected
MattermostMattermost10.11.0 <= 10.11.15affected
MattermostMattermost10.11.0 <= 10.11.16affected
MattermostMattermost11.7.0unaffected
MattermostMattermost11.6.2unaffected
MattermostMattermost11.5.5unaffected
MattermostMattermost10.11.16unaffected
MattermostMattermost10.11.17unaffected

Weaknesses

  • CWE-22: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

ADP Enrichment

CISA ADP Vulnrichment

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

References