CVE-2026-26204 (GCVE-0-2026-26204)

Vulnerability from cvelistv5 – Published: 2026-04-29 17:43 – Updated: 2026-04-30 12:48
VLAI
Title
Wazuh: Heap-based NULL WRITE Buffer Underflow in GetAlertData
Summary
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.
Severity
4.4 (Medium)
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-30 12:48 UTC
CWE
  • CWE-124 - Buffer Underwrite ('Buffer Underflow')
  • CWE-191 - Integer Underflow (Wrap or Wraparound)
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
wazuh wazuh Affected: >= 1.0.0, < 4.14.4
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