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TI-2025-08320 Aliases CVE-2025-9078GHSA-9p92-x77w-9fw2

Weak cache keys lead to post IDOR and link preview poisoning

Priority LOW 19CWE-328Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.10.x <= 10.10.1, 10.9.x <= 10.9.3 fail to properly validate cache keys for link metadata which allows authenticated users to access unauthorized posts and poison link previews via hash collision attacks on FNV-1 hashing

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00154 4th percentileScored 2026-11-07
Fix Fixed Mattermost (Mattermost): 10.11.0, 10.8.4, 10.5.9 +3github.com/mattermost/mattermost-server (Go): 10.8.4, 10.5.9, 9.11.18 +2+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
MattermostMattermost10.8.0 – 10.8.3; 10.5.0 – 10.5.8; 9.11.0 – 9.11.17; 10.10.0 – 10.10.1; 10.9.0 – 10.9.310.11.0, 10.8.4, 10.5.9, 9.11.18, 10.10.2, 10.9.4Patch availableCNA
—github.com/mattermost/mattermost-server (Go)10.8.0 to before 10.8.410.8.4Patch availableGHSA-9p92-x77w-9fw2
—github.com/mattermost/mattermost-server (Go)10.5.0 to before 10.5.910.5.9Patch availableGHSA-9p92-x77w-9fw2
—github.com/mattermost/mattermost-server (Go)9.11.0 to before 9.11.189.11.18Patch availableGHSA-9p92-x77w-9fw2
—github.com/mattermost/mattermost-server (Go)10.10.0 to before 10.10.210.10.2Patch availableGHSA-9p92-x77w-9fw2
—github.com/mattermost/mattermost-server (Go)10.9.0 to before 10.9.410.9.4Patch availableGHSA-9p92-x77w-9fw2
—github.com/mattermost/mattermost/server/v8 (Go)before 8.0.0-20250718075842-cd87e5c877378.0.0-20250718075842-cd87e5c87737Patch availableGHSA-9p92-x77w-9fw2
  • Mattermost VendorMattermost Affected 10.8.0 – 10.8.3; 10.5.0 – 10.5.8; 9.11.0 – 9.11.17; 10.10.0 – 10.10.1; 10.9.0 – 10.9.3 Fixed in 10.11.0, 10.8.4, 10.5.9, 9.11.18, 10.10.2, 10.9.4 Patch available CNA
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.8.0 to before 10.8.4 Fixed in 10.8.4 Patch available GHSA-9p92-x77w-9fw2
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.5.0 to before 10.5.9 Fixed in 10.5.9 Patch available GHSA-9p92-x77w-9fw2
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 9.11.0 to before 9.11.18 Fixed in 9.11.18 Patch available GHSA-9p92-x77w-9fw2
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.10.0 to before 10.10.2 Fixed in 10.10.2 Patch available GHSA-9p92-x77w-9fw2
  • github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.9.0 to before 10.9.4 Fixed in 10.9.4 Patch available GHSA-9p92-x77w-9fw2
  • github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20250718075842-cd87e5c87737 Fixed in 8.0.0-20250718075842-cd87e5c87737 Patch available GHSA-9p92-x77w-9fw2

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*9.11.0 to before 9.11.18; 10.5.0 to before 10.5.9; 10.8.0 to before 10.8.4; 10.9.0 to before 10.9.4; 10.10.0 to before 10.10.2VulnerableMattermost
  • cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 9.11.0 to before 9.11.18; 10.5.0 to before 10.5.9; 10.8.0 to before 10.8.4; 10.9.0 to before 10.9.4; 10.10.0 to before 10.10.2 Vulnerable ·Mattermost

Remediation

  • Fix · CNA Mattermost (Mattermost) Fixed in 10.11.0, 10.8.4, 10.5.9, 9.11.18, 10.10.2, 10.9.4
  • Fix · GHSA-9p92-x77w-9fw2 github.com/mattermost/mattermost-server (Go) Fixed in 10.8.4 Advisory →
  • Fix · GHSA-9p92-x77w-9fw2 github.com/mattermost/mattermost-server (Go) Fixed in 10.5.9 Advisory →
  • Fix · GHSA-9p92-x77w-9fw2 github.com/mattermost/mattermost-server (Go) Fixed in 9.11.18 Advisory →
  • Fix · GHSA-9p92-x77w-9fw2 github.com/mattermost/mattermost-server (Go) Fixed in 10.10.2 Advisory →
  • Fix · GHSA-9p92-x77w-9fw2 github.com/mattermost/mattermost-server (Go) Fixed in 10.9.4 Advisory →
  • Fix · GHSA-9p92-x77w-9fw2 github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20250718075842-cd87e5c87737 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-9078
  2. 2026-10-03 Alias added: GHSA-9p92-x77w-9fw2

References

Advisory 2

Other 5

  • 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