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TI-2025-27598 Aliases CVE-2025-41436GHSA-x3hx-ch7p-8xgg

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

VendorProductAffected versionsFixed inStatusSource
MattermostMattermost<11.0 – <11.011.0.0Patch availableCNA
—github.com/mattermost/mattermost-server (Go)before 11.0.0-alpha.111.0.0-alpha.1Patch availableGHSA-x3hx-ch7p-8xgg
—github.com/mattermost/mattermost/server/v8 (Go)before 8.0.0-20250815165020-c8d66301415d8.0.0-20250815165020-c8d66301415dPatch availableGHSA-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

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*before 11.0.0VulnerableMattermost
  • 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

  1. 2026-10-02 Threatist record created from CVE-2025-41436
  2. 2026-10-03 Alias added: GHSA-x3hx-ch7p-8xgg

References

  • 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
See all 505 →

Sources