TI-2025-34295 Aliases CVE-2025-54499 GHSA-xr3w-rmvj-f6m7

Insecure string comparison enables timing attacks

LOW 17CWE-208Published 2025-10-16 · Updated 2025-10-16

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: High
Impact type: Information disclosure
Confidentiality · integrity · availability: Low · None · None
Fix status: Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-208.

Summary

Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to use constant-time comparison for sensitive string comparisons which allows attackers to exploit timing oracles to perform byte-by-byte brute force attacks via response time analysis on Cloud API keys and OAuth client secrets

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00278 20th percentileScored 2026-11-07

Fix Fixed Mattermost (Mattermost): 10.12.0, 10.5.11, 10.11.3github.com/mattermost/mattermost/server/v8 (Go): 8.0.0-20250728063359-38208b8f065f+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

Vendor	Product	Affected versions	Fixed in	Status	Source
Mattermost	Mattermost	10.5.0 – 10.5.10; 10.11.0 – 10.11.2	10.12.0, 10.5.11, 10.11.3	Patch available	CNA
—	github.com/mattermost/mattermost/server/v8 (Go)	before 8.0.0-20250728063359-38208b8f065f	8.0.0-20250728063359-38208b8f065f	Patch available	GHSA-xr3w-rmvj-f6m7
—	github.com/mattermost/mattermost-server (Go)	10.5.0 to before 10.5.11	10.5.11	Patch available	GHSA-xr3w-rmvj-f6m7
—	github.com/mattermost/mattermost-server (Go)	10.11.0 to before 10.11.3	10.11.3	Patch available	GHSA-xr3w-rmvj-f6m7

Mattermost VendorMattermost Affected 10.5.0 – 10.5.10; 10.11.0 – 10.11.2 Fixed in 10.12.0, 10.5.11, 10.11.3 Patch available CNA
github.com/mattermost/mattermost/server/v8 (Go) Vendor— Affected before 8.0.0-20250728063359-38208b8f065f Fixed in 8.0.0-20250728063359-38208b8f065f Patch available GHSA-xr3w-rmvj-f6m7
github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.5.0 to before 10.5.11 Fixed in 10.5.11 Patch available GHSA-xr3w-rmvj-f6m7
github.com/mattermost/mattermost-server (Go) Vendor— Affected 10.11.0 to before 10.11.3 Fixed in 10.11.3 Patch available GHSA-xr3w-rmvj-f6m7

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:mattermost:mattermost_server::::::::	10.5.0 to before 10.5.11; 10.11.0 to before 10.11.3	Vulnerable	Mattermost

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* Versions 10.5.0 to before 10.5.11; 10.11.0 to before 10.11.3 Vulnerable ·Mattermost

Remediation

Fix · CNA Mattermost (Mattermost) Fixed in 10.12.0, 10.5.11, 10.11.3
Fix · GHSA-xr3w-rmvj-f6m7 github.com/mattermost/mattermost/server/v8 (Go) Fixed in 8.0.0-20250728063359-38208b8f065f Advisory →
Fix · GHSA-xr3w-rmvj-f6m7 github.com/mattermost/mattermost-server (Go) Fixed in 10.5.11 Advisory →
Fix · GHSA-xr3w-rmvj-f6m7 github.com/mattermost/mattermost-server (Go) Fixed in 10.11.3 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2025-54499
2026-10-03 Alias added: GHSA-xr3w-rmvj-f6m7

References

Advisory 2

Other 3

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