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TI-2024-27949 Aliases CVE-2024-41926GHSA-9fpw-c9x7-cv3j

Malicious remote can claim that a user was synced from another remote

Priority LOW 19CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-284.

Summary

Mattermost versions 9.9.x <= 9.9.0 and 9.5.x <= 9.5.6 fail to validate the source of sync messages and only allow the correct remote IDs, which allows a malicious remote to set arbitrary RemoteId values for synced users and therefore claim that a user was synced from another remote.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00175 6th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 9.10.0, 9.9.1, 9.5.7github.com/mattermost/mattermost/server/v8 (Go): 9.5.7, 9.9.1, 8.0.0-20240604093018-5114c3b7cdb8+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
MattermostMattermost9.9.0; 9.5.0 – 9.5.69.10.0, 9.9.1, 9.5.7Patch availableCNA
—github.com/mattermost/mattermost/server/v8 (Go)9.5.0 to before 9.5.79.5.7Patch availableGHSA-9fpw-c9x7-cv3j
—github.com/mattermost/mattermost/server/v8 (Go)9.9.0 to before 9.9.19.9.1Patch availableGHSA-9fpw-c9x7-cv3j
—github.com/mattermost/mattermost/server/v8 (Go)before 8.0.0-20240604093018-5114c3b7cdb88.0.0-20240604093018-5114c3b7cdb8Patch availableGHSA-9fpw-c9x7-cv3j
—github.com/mattermost/mattermost (Go)before 5.3.2-0.20240604093018-5114c3b7cdb85.3.2-0.20240604093018-5114c3b7cdb8Patch availableGHSA-9fpw-c9x7-cv3j
  • Mattermost VendorMattermost Affected 9.9.0; 9.5.0 – 9.5.6 Fixed in 9.10.0, 9.9.1, 9.5.7 Patch available CNA
  • github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected 9.5.0 to before 9.5.7 Fixed in 9.5.7 Patch available GHSA-9fpw-c9x7-cv3j
  • github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected 9.9.0 to before 9.9.1 Fixed in 9.9.1 Patch available GHSA-9fpw-c9x7-cv3j
  • github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20240604093018-5114c3b7cdb8 Fixed in 8.0.0-20240604093018-5114c3b7cdb8 Patch available GHSA-9fpw-c9x7-cv3j
  • github.com/mattermost/mattermost (Go) Vendor— Affected before 5.3.2-0.20240604093018-5114c3b7cdb8 Fixed in 5.3.2-0.20240604093018-5114c3b7cdb8 Patch available GHSA-9fpw-c9x7-cv3j

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*9.5.0 to before 9.5.7VulnerableMattermost
cpe:2.3:a:mattermost:mattermost_server:9.9.0:*:*:*:*:*:*:*9.9.0VulnerableMattermost
  • cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 9.5.0 to before 9.5.7 Vulnerable ·Mattermost
  • cpe:2.3:a:mattermost:mattermost_server:9.9.0:*:*:*:*:*:*:* Versions 9.9.0 Vulnerable ·Mattermost

Remediation

  • Fix · CNA Mattermost (Mattermost) Fixed in 9.10.0, 9.9.1, 9.5.7
  • Fix · GHSA-9fpw-c9x7-cv3j github.com/mattermost/mattermost/server/v8 (Go) Fixed in 9.5.7 Advisory →
  • Fix · GHSA-9fpw-c9x7-cv3j github.com/mattermost/mattermost/server/v8 (Go) Fixed in 9.9.1 Advisory →
  • Fix · GHSA-9fpw-c9x7-cv3j github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20240604093018-5114c3b7cdb8 Advisory →
  • Fix · GHSA-9fpw-c9x7-cv3j github.com/mattermost/mattermost (Go) Fixed in 5.3.2-0.20240604093018-5114c3b7cdb8 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-41926
  2. 2026-10-03 Alias added: GHSA-9fpw-c9x7-cv3j

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