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TI-2026-02092 Aliases CVE-2026-2463GHSA-fx49-m253-27jj

Unauthorized access to invite ID during team creation

Priority LOW 19CWE-862Published · 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-862.

Summary

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to filter invite IDs based on user permissions, which allows regular users to bypass access control restrictions and register unauthorized accounts via leaked invite IDs during team creation.. Mattermost Advisory ID: MMSA-2025-00565

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00177 7th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 11.4.0, 11.3.1, 11.2.3 +1github.com/mattermost/mattermost/server/v8 (Go): 8.0.0-20260105134819-cc427af41b2a+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
MattermostMattermost11.3.0 – 11.3.0; 11.2.0 – 11.2.2; 10.11.0 – 10.11.1011.4.0, 11.3.1, 11.2.3, 10.11.11Patch availableCNA
—github.com/mattermost/mattermost/server/v8 (Go)before 8.0.0-20260105134819-cc427af41b2a8.0.0-20260105134819-cc427af41b2aPatch availableGHSA-fx49-m253-27jj
—github.com/mattermost/mattermost-server (Go)before 5.3.2-0.20260105134819-cc427af41b2a5.3.2-0.20260105134819-cc427af41b2aPatch availableGHSA-fx49-m253-27jj
—github.com/mattermost/mattermost-server (Go)10.11.0-rc1 to before 10.11.1110.11.11Patch availableGHSA-fx49-m253-27jj
—github.com/mattermost/mattermost-server (Go)11.2.0-rc1 to before 11.2.311.2.3Patch availableGHSA-fx49-m253-27jj
—github.com/mattermost/mattermost-server (Go)11.3.0-rc1 to before 11.3.111.3.1Patch availableGHSA-fx49-m253-27jj
  • Mattermost VendorMattermost Affected 11.3.0 – 11.3.0; 11.2.0 – 11.2.2; 10.11.0 – 10.11.10 Fixed in 11.4.0, 11.3.1, 11.2.3, 10.11.11 Patch available CNA
  • github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20260105134819-cc427af41b2a Fixed in 8.0.0-20260105134819-cc427af41b2a Patch available GHSA-fx49-m253-27jj
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected before 5.3.2-0.20260105134819-cc427af41b2a Fixed in 5.3.2-0.20260105134819-cc427af41b2a Patch available GHSA-fx49-m253-27jj
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.11.0-rc1 to before 10.11.11 Fixed in 10.11.11 Patch available GHSA-fx49-m253-27jj
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 11.2.0-rc1 to before 11.2.3 Fixed in 11.2.3 Patch available GHSA-fx49-m253-27jj
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 11.3.0-rc1 to before 11.3.1 Fixed in 11.3.1 Patch available GHSA-fx49-m253-27jj

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*10.11.0 to before 10.11.11; 11.2.0 to before 11.2.3; 11.3.0 to before 11.3.1VulnerableMattermost
  • cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.11.0 to before 10.11.11; 11.2.0 to before 11.2.3; 11.3.0 to before 11.3.1 Vulnerable ·Mattermost

Remediation

  • Fix · CNA Mattermost (Mattermost) Fixed in 11.4.0, 11.3.1, 11.2.3, 10.11.11
  • Fix · GHSA-fx49-m253-27jj github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20260105134819-cc427af41b2a Advisory →
  • Fix · GHSA-fx49-m253-27jj github.com/mattermost/mattermost-server (Go) Fixed in 5.3.2-0.20260105134819-cc427af41b2a Advisory →
  • Fix · GHSA-fx49-m253-27jj github.com/mattermost/mattermost-server (Go) Fixed in 10.11.11 Advisory →
  • Fix · GHSA-fx49-m253-27jj github.com/mattermost/mattermost-server (Go) Fixed in 11.2.3 Advisory →
  • Fix · GHSA-fx49-m253-27jj github.com/mattermost/mattermost-server (Go) Fixed in 11.3.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-2463
  2. 2026-10-03 Alias added: GHSA-fx49-m253-27jj

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