CVE-2026-26204

Published Apr 29, 2026

Last updated 13 days ago

CVSS medium 4.4

Overview

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.
Source
security-advisories@github.com
NVD status
Analyzed
Products
wazuh

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

security-advisories@github.com
CWE-124

Social media

Hype score
Not currently trending

Configurations

Related CVEs

  1. 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.•CVE-2026-41499
  2. Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 4.4.0 to before version 4.14.4, a path traversal vulnerability in Wazuh's cluster synchronization extraction routine allows an authenticated cluster peer to write arbitrary files outside the intended extraction directory on other cluster nodes. This can be escalated to code execution in the Wazuh service context by overwriting Python modules loaded by Wazuh components (proof of concept available as separate attachment). In deployments where the cluster daemon runs with elevated privileges, system-level compromise is possible. This issue has been patched in version 4.14.4.•CVE-2026-30893
  3. Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 4.8.0 to before version 4.14.4, a stack-based buffer overflow exists in print_hex_string() in wazuh-remoted. The bug is triggered when formatting attacker-controlled bytes using sprintf(dst_buf + 2*i, "%.2x", src_buf[i]) on platforms where char is treated as signed and the compiled code sign-extends bytes before the variadic call. For input bytes such as 0xFF, the formatting can emit "ffffffff" (8 chars) instead of "ff" (2 chars), causing an out-of-bounds write past a fixed 2049-byte stack buffer. The vulnerable path is reachable remotely prior to any agent authentication/registration logic via TCP/1514 when an oversized length prefix causes the “unexpected message (hex)” diagnostic path to run. Additionally, the same unauthenticated oversized-message diagnostic path logs an attacker-controlled hex dump to /var/ossec/logs/ossec.log for each trigger, allowing remote log amplification that can degrade monitoring fidelity and consume disk/I/O. This log amplification is reachable even without triggering the sign-extension overflow (e.g., using bytes < 0x80). This issue has been patched in version 4.14.4.•CVE-2026-28221
  4. 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, Wazuh's server API brute-force protection for POST /security/user/authenticate can be bypassed by sending concurrent authentication requests. Although the configured threshold (max_login_attempts, default 50) is enforced correctly for sequential requests, a parallel burst allows significantly more failed login attempts to be processed before the IP block is applied. This enables an attacker to perform more password guesses than the configured policy intends (e.g., 100 attempts processed where 50 should be allowed). This issue has been patched in version 4.14.4.•CVE-2026-26206
  5. Wazuh provisioning scripts and Dockerfiles contain an insecure transport vulnerability where curl is invoked with the -k/--insecure flag, disabling SSL/TLS certificate validation. Attackers with network access can perform man-in-the-middle attacks to intercept and modify downloaded dependencies or code during the build process, leading to remote code execution and supply chain compromise.•CVE-2025-15612

References

Sources include official advisories and independent security research.