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TI-2025-27581 Aliases CVE-2025-41410GHSA-3q4q-wqm6-hvf3

Slack import bypasses email verification for team access controls

Priority LOW 24CWE-862Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · 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 10.10.x <= 10.10.2, 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to validate email ownership during Slack import process which allows attackers to create verified user accounts with arbitrary email domains via malicious Slack import data to bypass email-based team access restrictions

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00311 24th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 10.12.0, 10.10.3, 10.5.11 +1github.com/mattermost/mattermost/server/v8 (Go): 8.0.0-20250822083415-01b95392a450+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
MattermostMattermost10.10.0 – 10.10.2; 10.5.0 – 10.5.10; 10.11.0 – 10.11.210.12.0, 10.10.3, 10.5.11, 10.11.3Patch availableCNA
—github.com/mattermost/mattermost/server/v8 (Go)before 8.0.0-20250822083415-01b95392a4508.0.0-20250822083415-01b95392a450Patch availableGHSA-3q4q-wqm6-hvf3
—github.com/mattermost/mattermost-server (Go)10.10.0 to before 10.10.310.10.3Patch availableGHSA-3q4q-wqm6-hvf3
—github.com/mattermost/mattermost-server (Go)10.5.0 to before 10.5.1110.5.11Patch availableGHSA-3q4q-wqm6-hvf3
—github.com/mattermost/mattermost-server (Go)10.11.0 to before 10.11.310.11.3Patch availableGHSA-3q4q-wqm6-hvf3
  • Mattermost VendorMattermost Affected 10.10.0 – 10.10.2; 10.5.0 – 10.5.10; 10.11.0 – 10.11.2 Fixed in 10.12.0, 10.10.3, 10.5.11, 10.11.3 Patch available CNA
  • github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20250822083415-01b95392a450 Fixed in 8.0.0-20250822083415-01b95392a450 Patch available GHSA-3q4q-wqm6-hvf3
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.10.0 to before 10.10.3 Fixed in 10.10.3 Patch available GHSA-3q4q-wqm6-hvf3
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.5.0 to before 10.5.11 Fixed in 10.5.11 Patch available GHSA-3q4q-wqm6-hvf3
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.11.0 to before 10.11.3 Fixed in 10.11.3 Patch available GHSA-3q4q-wqm6-hvf3

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*10.5.0 to before 10.5.11; 10.10.0 to before 10.10.3; 10.11.0 to before 10.11.3VulnerableMattermost
  • cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.5.0 to before 10.5.11; 10.10.0 to before 10.10.3; 10.11.0 to before 10.11.3 Vulnerable ·Mattermost

Remediation

  • Fix · CNA Mattermost (Mattermost) Fixed in 10.12.0, 10.10.3, 10.5.11, 10.11.3
  • Fix · GHSA-3q4q-wqm6-hvf3 github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20250822083415-01b95392a450 Advisory →
  • Fix · GHSA-3q4q-wqm6-hvf3 github.com/mattermost/mattermost-server (Go) Fixed in 10.10.3 Advisory →
  • Fix · GHSA-3q4q-wqm6-hvf3 github.com/mattermost/mattermost-server (Go) Fixed in 10.5.11 Advisory →
  • Fix · GHSA-3q4q-wqm6-hvf3 github.com/mattermost/mattermost-server (Go) Fixed in 10.11.3 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-41410
  2. 2026-10-03 Alias added: GHSA-3q4q-wqm6-hvf3

References

Advisory 2

Other 4

  • 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