Mattermost GitHub Plugin allows unauthorized GitHub reactions via reaction forwarding hijacking
Priority LOW 14CWE-1287Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- Required
- Attack complexity
- High
- 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 10.11.x <= 10.11.6 and Mattermost GitHub plugin versions <=2.4.0 fail to validate plugin bot identity in reaction forwarding which allows attackers to hijack the GitHub reaction feature to make users add reactions to arbitrary GitHub objects via crafted notification posts.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00175 6th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 11.1.0, 10.11.7github.com/mattermost/mattermost/server/v8 (Go): 10.11.7-0.20251106103514-3b05384dd014+2 more products
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 | 10.11.0 – 10.11.6 | 11.1.0, 10.11.7 | Patch available | CNA |
| — | github.com/mattermost/mattermost/server/v8 (Go) | 10.11.0-rc1 to before 10.11.7-0.20251106103514-3b05384dd014 | 10.11.7-0.20251106103514-3b05384dd014 | Patch available | GHSA-jf5h-xfw4-p8gp |
| — | github.com/mattermost/mattermost (Go) | before 10.11.7-0.20251106103514-3b05384dd014 | 10.11.7-0.20251106103514-3b05384dd014 | Patch available | GHSA-jf5h-xfw4-p8gp |
| — | github.com/mattermost/mattermost (Go) | 11.0.0-alpha.1 to before 11.1.0 | 11.1.0 | Patch available | GHSA-jf5h-xfw4-p8gp |
| — | github.com/mattermost/mattermost-plugin-github (Go) | before 1.0.1-0.20250829075715-0deffcfc6bee | 1.0.1-0.20250829075715-0deffcfc6bee | Patch available | GHSA-jf5h-xfw4-p8gp |
- Mattermost VendorMattermost Affected 10.11.0 – 10.11.6 Fixed in 11.1.0, 10.11.7 Patch available CNA
- github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected 10.11.0-rc1 to before 10.11.7-0.20251106103514-3b05384dd014 Fixed in 10.11.7-0.20251106103514-3b05384dd014 Patch available GHSA-jf5h-xfw4-p8gp
- github.com/mattermost/mattermost (Go) Vendor— Affected before 10.11.7-0.20251106103514-3b05384dd014 Fixed in 10.11.7-0.20251106103514-3b05384dd014 Patch available GHSA-jf5h-xfw4-p8gp
- github.com/mattermost/mattermost (Go) Vendor— Affected 11.0.0-alpha.1 to before 11.1.0 Fixed in 11.1.0 Patch available GHSA-jf5h-xfw4-p8gp
- github.com/mattermost/mattermost-plugin-github (Go) Vendor— Affected before 1.0.1-0.20250829075715-0deffcfc6bee Fixed in 1.0.1-0.20250829075715-0deffcfc6bee Patch available GHSA-jf5h-xfw4-p8gp
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | 10.11.0 to before 10.11.7 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.11.0 to before 10.11.7 Vulnerable ·Mattermost
Remediation
- Fix · CNA Mattermost (Mattermost) Fixed in 11.1.0, 10.11.7
- Fix · GHSA-jf5h-xfw4-p8gp github.com/mattermost/mattermost/server/v8 (Go) Fixed in 10.11.7-0.20251106103514-3b05384dd014 Advisory →
- Fix · GHSA-jf5h-xfw4-p8gp github.com/mattermost/mattermost (Go) Fixed in 10.11.7-0.20251106103514-3b05384dd014 Advisory →
- Fix · GHSA-jf5h-xfw4-p8gp github.com/mattermost/mattermost (Go) Fixed in 11.1.0 Advisory →
- Fix · GHSA-jf5h-xfw4-p8gp github.com/mattermost/mattermost-plugin-github (Go) Fixed in 1.0.1-0.20250829075715-0deffcfc6bee Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-13352
- 2026-10-03 Alias added: GHSA-jf5h-xfw4-p8gp
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-2025-13352 · CVE Program
- CVE-2025-13352 · NVD
- FIRST EPSS
- GHSA-jf5h-xfw4-p8gp · GitHub Advisory Database · CC BY 4.0
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