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 (`wdb_delta_event.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.