CVE-2026-28732

Summary

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to enforce slash command trigger-word uniqueness during command updates which allows an authenticated team member with Manage Own Slash Commands permission to hijack and impersonate existing system or custom slash commands via editing their own slash command trigger to an already-registered trigger through the command update API. Mattermost Advisory ID: MMSA-2026-00597

Affected Software

VendorProductVersion RangeStatus
MattermostMattermost11.5.0 <= 11.5.1affected
MattermostMattermost10.11.0 <= 10.11.13affected
MattermostMattermost11.4.0 <= 11.4.3affected
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