Path traversal in image upload with preview overwrite
Priority LOW 21CWE-22Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.
Summary
Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 10.10.x <= 10.10.0, 10.9.x <= 10.9.3 fail to sanitize file names which allows users with file upload permission to overwrite file attachment thumbnails via path traversal in file streaming APIs.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00765 55th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 10.11.0, 10.8.4, 10.5.9 +2github.com/mattermost/mattermost-server (Go): 10.8.4, 10.5.9, 10.9.4 +1+1 more product
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 | 10.8.0 – 10.8.3; 10.5.0 – 10.5.8; 10.10.0; 10.9.0 – 10.9.3 | 10.11.0, 10.8.4, 10.5.9, 10.10.1, 10.9.4 | Patch available | CNA |
| — | github.com/mattermost/mattermost-server (Go) | 10.8.0 to before 10.8.4 | 10.8.4 | Patch available | GHSA-pj6f-rc94-gw53 |
| — | github.com/mattermost/mattermost-server (Go) | 10.5.0 to before 10.5.9 | 10.5.9 | Patch available | GHSA-pj6f-rc94-gw53 |
| — | github.com/mattermost/mattermost-server (Go) | 10.9.0 to before 10.9.4 | 10.9.4 | Patch available | GHSA-pj6f-rc94-gw53 |
| — | github.com/mattermost/mattermost-server (Go) | 10.10.0 to before 10.10.1 | 10.10.1 | Patch available | GHSA-pj6f-rc94-gw53 |
| — | github.com/mattermost/mattermost/server/v8 (Go) | before 8.0.0-20250708173752-d6b35c41f0ae5 | 8.0.0-20250708173752-d6b35c41f0ae5 | Patch available | GHSA-pj6f-rc94-gw53 |
- Mattermost VendorMattermost Affected 10.8.0 – 10.8.3; 10.5.0 – 10.5.8; 10.10.0; 10.9.0 – 10.9.3 Fixed in 10.11.0, 10.8.4, 10.5.9, 10.10.1, 10.9.4 Patch available CNA
- github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.8.0 to before 10.8.4 Fixed in 10.8.4 Patch available GHSA-pj6f-rc94-gw53
- github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.5.0 to before 10.5.9 Fixed in 10.5.9 Patch available GHSA-pj6f-rc94-gw53
- github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.9.0 to before 10.9.4 Fixed in 10.9.4 Patch available GHSA-pj6f-rc94-gw53
- github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.10.0 to before 10.10.1 Fixed in 10.10.1 Patch available GHSA-pj6f-rc94-gw53
- github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20250708173752-d6b35c41f0ae5 Fixed in 8.0.0-20250708173752-d6b35c41f0ae5 Patch available GHSA-pj6f-rc94-gw53
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | 10.5.0 to before 10.5.9; 10.8.0 to before 10.8.4; 10.9.0 to before 10.9.4 | Vulnerable | Mattermost |
| cpe:2.3:a:mattermost:mattermost_server:10.10.0:-:*:*:*:*:*:* | 10.10.0 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.5.0 to before 10.5.9; 10.8.0 to before 10.8.4; 10.9.0 to before 10.9.4 Vulnerable ·Mattermost
- cpe:2.3:a:mattermost:mattermost_server:10.10.0:-:*:*:*:*:*:* Versions 10.10.0 Vulnerable ·Mattermost
Remediation
- Fix · CNA Mattermost (Mattermost) Fixed in 10.11.0, 10.8.4, 10.5.9, 10.10.1, 10.9.4
- Fix · GHSA-pj6f-rc94-gw53 github.com/mattermost/mattermost-server (Go) Fixed in 10.8.4 Advisory →
- Fix · GHSA-pj6f-rc94-gw53 github.com/mattermost/mattermost-server (Go) Fixed in 10.5.9 Advisory →
- Fix · GHSA-pj6f-rc94-gw53 github.com/mattermost/mattermost-server (Go) Fixed in 10.9.4 Advisory →
- Fix · GHSA-pj6f-rc94-gw53 github.com/mattermost/mattermost-server (Go) Fixed in 10.10.1 Advisory →
- Fix · GHSA-pj6f-rc94-gw53 github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20250708173752-d6b35c41f0ae5 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-6465
- 2026-10-03 Alias added: GHSA-pj6f-rc94-gw53
References
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-2025-6465 · CVE Program
- CVE-2025-6465 · NVD
- FIRST EPSS
- GHSA-pj6f-rc94-gw53 · 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