Vulnerability Description
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2 fail to verify run_create permission for empty playbookId, which allows team members to create unauthorized runs via the playbook run API. Mattermost Advisory ID: MMSA-2025-00542
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost Server | >= 11.2.0, < 11.2.3 |
Related Weaknesses (CWE)
References
- https://mattermost.com/security-updatesVendor Advisory
FAQ
What is CVE-2026-26304?
CVE-2026-26304 is a vulnerability with a CVSS score of 4.3 (MEDIUM). Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2 fail to verify run_create permission for empty playbookId, which allows team members to create unauthorized runs via the playbook run API. Matter...
How severe is CVE-2026-26304?
CVE-2026-26304 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-2026-26304?
Check the references section above for vendor advisories and patch information. Affected products include: Mattermost Mattermost Server.