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

Vulnerability summary

CVE-2026-25772 is a high (CVSS 7.2) Stack-based Buffer Overflow vulnerability in wazuh. EPSS estimates a 0.51% chance of exploitation in the next 30 days, higher than 42.8% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 17-03-2026
   PublishedVulnerability first disclosed.
2. 17-03-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-121Stack-based Buffer OverflowA stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
• CWE-191Integer Underflow (Wrap or Wraparound)The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.