CVE-2021-20038 : Security Advisory and Response

A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.

Understanding CVE-2021-20038

This section provides detailed insights into the CVE-2021-20038 vulnerability.

What is CVE-2021-20038?

CVE-2021-20038 is a Stack-based buffer overflow vulnerability in the SMA100 Apache httpd server's mod_cgi module environment variables.

The Impact of CVE-2021-20038

The vulnerability allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the affected SonicWall SMA100 appliances.

Technical Details of CVE-2021-20038

This section covers the technical aspects of CVE-2021-20038.

Vulnerability Description

The vulnerability lies in the mod_cgi module environment variables of the SMA100 Apache httpd server, resulting in a Stack-based buffer overflow.

Affected Systems and Versions

SonicWall SMA100 appliances running firmware versions 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv, and earlier are affected by CVE-2021-20038.

Exploitation Mechanism

Remote unauthenticated attackers can exploit this vulnerability to execute code as a 'nobody' user in the affected appliances.

Mitigation and Prevention

In this section, we discuss mitigation strategies and preventive measures for CVE-2021-20038.

Immediate Steps to Take

It is recommended to apply security patches provided by SonicWall to address the vulnerability promptly.

Long-Term Security Practices

Implementing network segmentation, access controls, and security monitoring can enhance the overall security posture.

Patching and Updates

Regularly update the firmware of affected SMA100 appliances to ensure protection against known vulnerabilities.