CVE-2021-20038
Published on December 8, 2021

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.

Vendor Advisory NVD

Known Exploited Vulnerability

This SonicWall SMA 100 Appliances Stack-Based Buffer Overflow Vulnerability is part of CISA's list of Known Exploited Vulnerabilities. SonicWall SMA 100 devies are vulnerable to an unauthenticated stack-based buffer overflow vulnerability where exploitation can result in code execution.

The following remediation steps are recommended / required by February 11, 2022: Apply updates per vendor instructions.

Vulnerability Analysis

CVE-2021-20038 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. It has the highest possible exploitability rating (3.9). The potential impact of an exploit of this vulnerability is considered to be critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.

What is a Memory Corruption Vulnerability?

The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.

CVE-2021-20038 has been classified to as a Memory Corruption vulnerability or weakness.


Products Associated with CVE-2021-20038

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What versions are vulnerable to CVE-2021-20038?

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