Vulnerability · Published Jul 16, 2026 · Assigned by GitHub_M

CVE-2026-40106Wazuh: Heap-based Buffer Overflow in syscheck Registry Wildcard Expansion (LPE / DoS)

Medium 4.7

In plain English

A medium-severity heap buffer overflow in wazuh from wazuh. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities).

Severity (CVSS 3.1)4.7Medium
Exploit odds (30 days)0.1%top 97.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Wazuh is a free and open source platform used for threat prevention, detection, and response. Versions 4.6.0 and above prior to 4.14.5 contain a heap-based buffer overflow vulnerability in the syscheck component of the Wazuh agent for Windows. When expanding registry paths containing wildcards (* or ?), the agent allocates a fixed-size heap buffer of 256 bytes (OS_SIZE_256). By creating a registry subkey with a maximum allowed length (255 characters) inside a monitored path, a low-privileged local attacker can force an out-of-bounds write during string concatenation. Since wazuh-agent.exe runs as NT AUTHORITY\SYSTEM, this can lead to a silent Denial of Service (blinding the agent) or potentially Local Privilege Escalation (LPE). This issue has been fixed in version 4.14.5.

Affected products (as reported)

VendorProductVersions
wazuh wazuh >= 4.6.0, < 4.14.5

Weakness: CWE-122 · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

References