CVE-2026-3112
Mattermost allows system administrators to read arbitrary host files via malicious AdvancedLoggingJSON configuration
6.8
MEDIUM
CVSS 3.1
EPSS 0.02%
Description
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate Advanced Logging file target paths which allows system administrators to read arbitrary host files via malicious AdvancedLoggingJSON configuration in support packet generation. Mattermost Advisory ID: MMSA-2025-00562.
How to fix CVE-2026-3112
To remediate CVE-2026-3112, upgrade the affected package to a fixed version below.
- —upgrade to 11.4.1 or later
Is CVE-2026-3112 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- >= 11.4.0-rc1, < 11.4.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.8 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N |