CVE-2026-26204

MEDIUM

Wazuh: Heap-based NULL WRITE Buffer Underflow in GetAlertData

Title source: cna
STIX 2.1

Description

Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 1.0.0 to before version 4.14.4, a heap-based out-of-bounds WRITE occurs in GetAlertData, resulting in writing a NULL byte exactly 1 byte before the start of the buffer allocated by strdup. Due to unsigned integer underflow and pointer arithmetic wrapping, the write lands at offset -1 from the buffer, corrupting heap metadata. A malicious actor can potentially leverage this issue through a compromised agent to cause denial of service or heap corruption by injecting a specially crafted alert into the alerts log file monitored by wazuh-logcollector. This issue has been patched in version 4.14.4.

References (2)

Core 2
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/wazuh/wazuh/releases/tag/v4.14.4

Scores

CVSS v3 4.4
EPSS 0.0017
EPSS Percentile 6.5%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-124 CWE-191
Status published
Products (2)
wazuh/wazuh 1.0.0 - 4.14.4
wazuh/wazuh >= 1.0.0, < 4.14.4
Published Apr 29, 2026
Tracked Since Apr 29, 2026