Unauthorized access to archived channel content via threads interface
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
- Low · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-863.
Summary
Mattermost versions <11.0 fail to properly enforce the "Allow users to view archived channels" setting which allows regular users to access archived channel content and files via the "Open in Channel" functionality from followed threads
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00181 7th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 11.0.0github.com/mattermost/mattermost-server (Go): 11.0.0-alpha.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 | <11.0 – <11.0 | 11.0.0 | Patch available | CNA |
| — | github.com/mattermost/mattermost-server (Go) | before 11.0.0-alpha.1 | 11.0.0-alpha.1 | Patch available | GHSA-x3hx-ch7p-8xgg |
| — | github.com/mattermost/mattermost/server/v8 (Go) | before 8.0.0-20250815165020-c8d66301415d | 8.0.0-20250815165020-c8d66301415d | Patch available | GHSA-x3hx-ch7p-8xgg |
- Mattermost VendorMattermost Affected <11.0 – <11.0 Fixed in 11.0.0 Patch available CNA
- github.com/mattermost/mattermost-server (Go) Vendor— Affected before 11.0.0-alpha.1 Fixed in 11.0.0-alpha.1 Patch available GHSA-x3hx-ch7p-8xgg
- github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20250815165020-c8d66301415d Fixed in 8.0.0-20250815165020-c8d66301415d Patch available GHSA-x3hx-ch7p-8xgg
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | before 11.0.0 | Vulnerable | Mattermost |
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions before 11.0.0 Vulnerable ·Mattermost
Remediation
- Fix · CNA Mattermost (Mattermost) Fixed in 11.0.0
- Fix · GHSA-x3hx-ch7p-8xgg github.com/mattermost/mattermost-server (Go) Fixed in 11.0.0-alpha.1 Advisory →
- Fix · GHSA-x3hx-ch7p-8xgg github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20250815165020-c8d66301415d Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-41436
- 2026-10-03 Alias added: GHSA-x3hx-ch7p-8xgg
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-2025-41436 · CVE Program
- CVE-2025-41436 · NVD
- FIRST EPSS
- GHSA-x3hx-ch7p-8xgg · 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