Wazuh: Multiple Heap-based NULL WRITE Buffer Underflows in parse_uname_string()
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-191 and the CVSS impact.
Summary
Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 4.0.0 to before version 4.14.4, multiple heap-based out-of-bounds WRITE vulnerabilities exist in parse_uname_string() (remoted_op.c). This function processes OS identification data from agents and contains a dangerous code pattern that appears in 4 locations within the same function: writing to strlen(ptr) - 1 without checking for empty strings. When the string is empty, strlen() returns 0, and 0 - 1 wraps to SIZE_MAX due to unsigned integer underflow. Due to pointer arithmetic wrapping, SIZE_MAX effectively becomes -1, causing a write exactly 1 byte before the allocated buffer. This corrupts heap metadata (e.g., the chunk size field in glibc malloc), leading to heap corruption. This issue has been patched in version 4.14.4.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA wazuh (wazuh) Fixed in 4.14.4
Timeline
- 2026-10-02 Threatist record created from CVE-2026-41499
References
More Wazuh vulnerabilities
- TI-2025-17783 Remote code execution in Wazuh server KEVCVSS 3.1CRITICAL 9.9
- TI-2026-23722 Path traversal in wazuh CVSS 3.1CRITICAL 9.9
- TI-2024-01157 Remote code execution and local privilege escalation in Wazuh Windows agent via NetNTLMv2 hash theft CVSS 4.0CRITICAL 9.5
- TI-2026-22556 Wazuh: Pre-auth stack-based buffer overflow in wazuh-remoted print_hex_string() due to signed char promotion on x86_64 CVSS 3.1HIGH 8.2
- TI-2026-35598 Wazuh: cluster peer can read arbitrary master files and forge offline REST API… CVSS 3.1CRITICAL 9.1
- TI-2026-35467 Wazuh: merged-file header path traversal in cluster sync allows arbitrary file write under WAZUH_PATH in Wazuh manager CVSS 3.1CRITICAL 9.1
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences