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TI-2025-10796 Aliases CVE-2025-11776GHSA-j6gg-r5jc-47cm

Guest user can discover archived public channels

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 · CNA. Fix status from CNA and GitHub. Impact type from CWE-863.

Summary

Mattermost versions <11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the `/api/v4/teams/{team_id}/channels/search_archived` endpoint

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00208 10th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 11.0.0github.com/mattermost/mattermost/server/v8 (Go): 8.0.0-20250815165020-c8d66301415d+4 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

VendorProductAffected versionsFixed inStatusSource
MattermostMattermost<11 – <1111.0.0Patch availableCNA
—github.com/mattermost/mattermost/server/v8 (Go)before 8.0.0-20250815165020-c8d66301415d8.0.0-20250815165020-c8d66301415dPatch availableGHSA-j6gg-r5jc-47cm
—github.com/mattermost/mattermost (Go)before 5.3.2-0.20250815165020-c8d66301415d5.3.2-0.20250815165020-c8d66301415dPatch availableGHSA-j6gg-r5jc-47cm
—github.com/mattermost/mattermost-server (Go)before 5.3.2-0.20250815165020-c8d66301415d5.3.2-0.20250815165020-c8d66301415dPatch availableGHSA-j6gg-r5jc-47cm
—github.com/mattermost/mattermost-server/v5 (Go)before 5.3.2-0.20250815165020-c8d66301415d5.3.2-0.20250815165020-c8d66301415dPatch availableGHSA-j6gg-r5jc-47cm
—github.com/mattermost/mattermost-server/v6 (Go)before 5.3.2-0.20250815165020-c8d66301415d5.3.2-0.20250815165020-c8d66301415dPatch availableGHSA-j6gg-r5jc-47cm
  • Mattermost VendorMattermost Affected <11 – <11 Fixed in 11.0.0 Patch available CNA
  • 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-j6gg-r5jc-47cm
  • github.com/mattermost/mattermost (Go) Vendor— Affected before 5.3.2-0.20250815165020-c8d66301415d Fixed in 5.3.2-0.20250815165020-c8d66301415d Patch available GHSA-j6gg-r5jc-47cm
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected before 5.3.2-0.20250815165020-c8d66301415d Fixed in 5.3.2-0.20250815165020-c8d66301415d Patch available GHSA-j6gg-r5jc-47cm
  • github.com/mattermost/mattermost-server/v5 (Go) Vendor— Affected before 5.3.2-0.20250815165020-c8d66301415d Fixed in 5.3.2-0.20250815165020-c8d66301415d Patch available GHSA-j6gg-r5jc-47cm
  • github.com/mattermost/mattermost-server/v6 (Go) Vendor— Affected before 5.3.2-0.20250815165020-c8d66301415d Fixed in 5.3.2-0.20250815165020-c8d66301415d Patch available GHSA-j6gg-r5jc-47cm

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-j6gg-r5jc-47cm github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20250815165020-c8d66301415d Advisory →
  • Fix · GHSA-j6gg-r5jc-47cm github.com/mattermost/mattermost (Go) Fixed in 5.3.2-0.20250815165020-c8d66301415d Advisory →
  • Fix · GHSA-j6gg-r5jc-47cm github.com/mattermost/mattermost-server (Go) Fixed in 5.3.2-0.20250815165020-c8d66301415d Advisory →
  • Fix · GHSA-j6gg-r5jc-47cm github.com/mattermost/mattermost-server/v5 (Go) Fixed in 5.3.2-0.20250815165020-c8d66301415d Advisory →
  • Fix · GHSA-j6gg-r5jc-47cm github.com/mattermost/mattermost-server/v6 (Go) Fixed in 5.3.2-0.20250815165020-c8d66301415d Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-11776
  2. 2026-10-03 Alias added: GHSA-j6gg-r5jc-47cm

References

Advisory 2

Other 1

  • 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

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences