Inconsistent authorization checks in Mattermost Boards endpoints
Priority LOW 20CWE-862Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-862.
Summary
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to enforce the board-creation permission which allows an unauthorized authenticated user to create boards via the board duplicate, boards-and-blocks, and archive-import endpoints.. Mattermost Advisory ID: MMSA-2026-00715
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00254 17th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 11.10.0, 11.9.1, 11.8.5 +2
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Mattermost | Mattermost | 11.9.0 – 11.9.0; 11.8.0 – 11.8.4; 11.7.0 – 11.7.7; 10.11.0 – 10.11.22 | 11.10.0, 11.9.1, 11.8.5, 11.7.8, 10.11.23 | Patch available | CNA |
- Mattermost VendorMattermost Affected 11.9.0 – 11.9.0; 11.8.0 – 11.8.4; 11.7.0 – 11.7.7; 10.11.0 – 10.11.22 Fixed in 11.10.0, 11.9.1, 11.8.5, 11.7.8, 10.11.23 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | 10.11.0 to before 10.11.23; 11.7.0 to before 11.7.8; 11.8.0 to before 11.8.5; 11.9.0 to before 11.9.1 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.11.0 to before 10.11.23; 11.7.0 to before 11.7.8; 11.8.0 to before 11.8.5; 11.9.0 to before 11.9.1 Vulnerable ·Mattermost
Remediation
- Fix · CNA Mattermost (Mattermost) Fixed in 11.10.0, 11.9.1, 11.8.5, 11.7.8, 10.11.23
Timeline
- 2026-10-02 Threatist record created from CVE-2026-14344
- 2026-10-03 Alias added: GHSA-mcg5-jcfq-qfh6
References
Advisory 1
More Mattermost Server vulnerabilities
- TI-2025-18933 Arbitrary file read in Mattermost Boards via import & export board archive CVSS 3.1CRITICAL 9.9
- TI-2025-04465 Path Traversal Leading to RCE by Any Authenticated Mattermost User CVSS 3.1CRITICAL 9.9
- TI-2017-14068 An issue was discovered in Mattermost Server before 3.6.2. CVSS 3.1CRITICAL 9.8
- TI-2017-14060 An issue was discovered in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7. CVSS 3.1CRITICAL 9.8
- TI-2017-14048 An issue was discovered in Mattermost Server before 4.1.0, 4.0.4, and 3.10.3. CVSS 3.1CRITICAL 9.8
- TI-2025-14360 Arbitrary file read via block duplication in Mattermost Boards CVSS 3.1CRITICAL 9.9
Sources
- CVE-2026-14344 · CVE Program
- CVE-2026-14344 · NVD
- FIRST EPSS
- GHSA-mcg5-jcfq-qfh6 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences