VA MAX RCE Vulnerability (CVE-2019-25671)

Overview

A high-severity remote code execution (RCE) vulnerability, identified as CVE-2019-25671, affects VA MAX version 8.3.4. This flaw allows an authenticated attacker to execute arbitrary operating system commands on the server by exploiting insufficient input validation in a specific parameter.

Vulnerability Details

The vulnerability exists in the changeip.php endpoint. An attacker can send a specially crafted POST request containing shell metacharacters in the mtu_eth0 parameter. Because the application does not properly sanitize this input, these metacharacters are passed to the underlying system shell, allowing the execution of arbitrary commands. Successful exploitation runs these commands with the privileges of the apache user.

Impact

If exploited, this vulnerability grants an attacker the ability to run any command on the affected server. This could lead to a full compromise of the system, including data theft, installation of malware or backdoors, and lateral movement within the network. The requirement for authentication does limit the attack surface, but any compromised user account could be leveraged for this attack. For context on the damage caused by server compromises, recent incidents are detailed in our breach reports.

Remediation and Mitigation

The primary remediation is to apply the official patch or upgrade to a version of VA MAX that addresses this vulnerability. Users should consult the vendor for the specific fixed version.

If immediate patching is not possible, consider these mitigation steps:

• Restrict network access to the VA MAX administrative interface to only trusted IP addresses.
• Implement a Web Application Firewall (WAF) configured to block requests containing shell metacharacters.
• Ensure user accounts with access to the system are secured with strong, unique passwords and follow the principle of least privilege.
• Monitor web server logs for suspicious POST requests to changeip.php containing unusual characters in parameters.

For ongoing updates on such threats, follow our security news.

Security Insight

This vulnerability is a classic example of command injection, a flaw that has plagued web applications for decades. Its presence in a network management product like VA MAX is particularly concerning, as these systems are often deployed in sensitive perimeter or internal network segments. The persistence of such basic input validation failures in modern software highlights a continued gap in secure development lifecycle (SDLC) practices, even for vendors producing critical infrastructure tools.

Further Reading

• All High Vulnerabilities
• Recent Critical Vulnerabilities
• Top Critical CVEs