CVE-2026-40106

MEDIUM

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

Title source: cna
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 4.7
EPSS 0.0013
EPSS Percentile 2.8%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-122
Status published
Products (2)
wazuh/wazuh 4.6.0 - 4.14.5
wazuh/wazuh >= 4.6.0, < 4.14.5
Published Jul 17, 2026
Tracked Since Jul 17, 2026