CVE-2026-25772: Wazuh Database Synchronization Vulnerable to Stack-based Buffer Overflow via snprintf Integer Underflow

Wazuh is a free and open source platform used for threat prevention, detection, and response. Starting in version 4.4.0 and prior to version 4.14.3, a stack-based buffer overflow vulnerability exists in the Wazuh Database synchronization module (wdbdeltaevent.c). The SQL query construction logic allows for an integer underflow when calculating the remaining buffer size. This occurs because the code incorrectly aggregates the return value of snprintf. If a specific database synchronization payload exceeds the size of the query buffer (2048 bytes), the size calculation wraps around to a massive integer, effectively removing bounds checking for subsequent writes. This allows an attacker to corrupt the stack, leading to a Denial of Service (DoS) or potentially RCE. Version 4.14.3 fixes the issue.