Insecure Direct Object Reference in Mattermost Boards Plugin Enables Unauthorised Comment Deletion
Priority LOW 19CWE-863Published · 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 and GitHub. Impact type from CWE-863.
Summary
Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to validate user permissions when deleting comments in Boards, which allows an authenticated user with the editor role to delete comments created by other users.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00196 9th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 11.1.0, 11.0.3, 10.12.2 +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 | 11.0.0 – 11.0.2; 10.12.0 – 10.12.1; 10.11.0 – 10.11.4; 10.5.0 – 10.5.12 | 11.1.0, 11.0.3, 10.12.2, 10.11.5, 10.5.13 | Patch available | CNA |
| — | github.com/mattermost/mattermost/server/v8 (Go) | up to 8.0.0-20251013062617-7977e7e6dae3 | — | No fix listed | GHSA-p6gj-jc38-x2m7 |
| — | github.com/mattermost/mattermost (Go) | 10.11.0 – 10.11.4 | — | No fix listed | GHSA-p6gj-jc38-x2m7 |
| — | github.com/mattermost/mattermost (Go) | 10.12.0 – 10.12.1 | — | No fix listed | GHSA-p6gj-jc38-x2m7 |
| — | github.com/mattermost/mattermost (Go) | 10.5.0 – 10.5.12 | — | No fix listed | GHSA-p6gj-jc38-x2m7 |
| — | github.com/mattermost/mattermost (Go) | 11.0.0 – 11.0.2 | — | No fix listed | GHSA-p6gj-jc38-x2m7 |
- Mattermost VendorMattermost Affected 11.0.0 – 11.0.2; 10.12.0 – 10.12.1; 10.11.0 – 10.11.4; 10.5.0 – 10.5.12 Fixed in 11.1.0, 11.0.3, 10.12.2, 10.11.5, 10.5.13 Patch available CNA
- github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected up to 8.0.0-20251013062617-7977e7e6dae3 Fixed in — No fix listed GHSA-p6gj-jc38-x2m7
- github.com/mattermost/mattermost (Go) Vendor— Affected 10.11.0 – 10.11.4 Fixed in — No fix listed GHSA-p6gj-jc38-x2m7
- github.com/mattermost/mattermost (Go) Vendor— Affected 10.12.0 – 10.12.1 Fixed in — No fix listed GHSA-p6gj-jc38-x2m7
- github.com/mattermost/mattermost (Go) Vendor— Affected 10.5.0 – 10.5.12 Fixed in — No fix listed GHSA-p6gj-jc38-x2m7
- github.com/mattermost/mattermost (Go) Vendor— Affected 11.0.0 – 11.0.2 Fixed in — No fix listed GHSA-p6gj-jc38-x2m7
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | 10.5.0 to before 10.5.13; 10.11.0 to before 10.11.5; 10.12.0 to before 10.12.2; 11.0.0 to before 11.0.3 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.5.0 to before 10.5.13; 10.11.0 to before 10.11.5; 10.12.0 to before 10.12.2; 11.0.0 to before 11.0.3 Vulnerable ·Mattermost
Remediation
- Fix · CNA Mattermost (Mattermost) Fixed in 11.1.0, 11.0.3, 10.12.2, 10.11.5, 10.5.13
Timeline
- 2026-10-02 Threatist record created from CVE-2025-12756
- 2026-10-03 Alias added: GHSA-p6gj-jc38-x2m7
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-2025-12756 · CVE Program
- CVE-2025-12756 · NVD
- FIRST EPSS
- GHSA-p6gj-jc38-x2m7 · 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