SECURELYN

CVE-2026-74040

Wazuh versions from 3.9.0 before 4.14.8 contain an arbitrary file overwrite vulnerability in MasterHandler.process_files_from_worker allowing a cluster worker to overwrite protected master files. Attackers controlling a worker can use a trailing-slash basename bypass and missing extra_valid enforcement to overwrite ossec.conf and agent.conf, achieving root remote code execution across the manager and every agent.

Scores

9.4
CVSS 9.4 out of 10, critical severity.
0.6%
EPSS 0.6% chance of exploitation in the next 30 days.

The facts

Published
13 October 2026
Last changed
16 October 2026
NVD status
Awaiting Analysis
Severity
Critical, CVSS 9.4 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R…
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.6% chance of exploitation activity in the next 30 days (percentile 45).

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References