Vulnerability Description
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
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost Server | >= 10.11.0, < 10.11.14 |
Related Weaknesses (CWE)
References
- https://mattermost.com/security-updatesVendor Advisory
FAQ
What is CVE-2026-28732?
CVE-2026-28732 is a vulnerability with a CVSS score of 4.3 (MEDIUM). 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 ...
How severe is CVE-2026-28732?
CVE-2026-28732 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-28732?
Check the references section above for vendor advisories and patch information. Affected products include: Mattermost Mattermost Server.