CVE-2021-20038: SonicWall SMA 100 Appliances Stack-Based Buffer Overflow Vulnerability

Published Dec 8, 2021
·
Updated

A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's modcgi 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.

Other sources

SonicWall SMA 100 devies are vulnerable to an unauthenticated stack-based buffer overflow vulnerability where exploitation can result in code execution.

CISA

Affected Software

41 affected components
SonicWall Sma 200 Firmware=10.2.0.8-37sv
SonicWall Sma 200 Firmware=10.2.1.1-19sv
SonicWall Sma 200 Firmware=10.2.1.2-24sv
SonicWall SMA 200
SonicWall Sma 210 Firmware=10.2.0.8-37sv
SonicWall Sma 210 Firmware=10.2.1.1-19sv
SonicWall Sma 210 Firmware=10.2.1.2-24sv
SonicWall Sma 210
SonicWall Sma 410 Firmware=10.2.0.8-37sv
SonicWall Sma 410 Firmware=10.2.1.1-19sv
SonicWall Sma 410 Firmware=10.2.1.2-24sv
SonicWall Sma 410
SonicWall Sma 400 Firmware=10.2.0.8-37sv
SonicWall Sma 400 Firmware=10.2.1.1-19sv
SonicWall Sma 400 Firmware=10.2.1.2-24sv
SonicWall Sma 400
SonicWall Sma 500v Firmware=10.2.0.8-37sv
SonicWall Sma 500v Firmware=10.2.1.1-19sv
SonicWall Sma 500v Firmware=10.2.1.2-24sv
SonicWall Sma 500v
SonicWall SMA 100 Appliances
All of the following
Any of the following
SonicWall Sma 200 Firmware=10.2.0.8-37sv
SonicWall Sma 200 Firmware=10.2.1.1-19sv
SonicWall Sma 200 Firmware=10.2.1.2-24sv
SonicWall SMA 200
All of the following
Any of the following
SonicWall Sma 210 Firmware=10.2.0.8-37sv
SonicWall Sma 210 Firmware=10.2.1.1-19sv
SonicWall Sma 210 Firmware=10.2.1.2-24sv
SonicWall Sma 210
All of the following
Any of the following
SonicWall Sma 410 Firmware=10.2.0.8-37sv
SonicWall Sma 410 Firmware=10.2.1.1-19sv
SonicWall Sma 410 Firmware=10.2.1.2-24sv
SonicWall Sma 410
All of the following
Any of the following
SonicWall Sma 400 Firmware=10.2.0.8-37sv
SonicWall Sma 400 Firmware=10.2.1.1-19sv
SonicWall Sma 400 Firmware=10.2.1.2-24sv
SonicWall Sma 400
All of the following
Any of the following
SonicWall Sma 500v Firmware=10.2.0.8-37sv
SonicWall Sma 500v Firmware=10.2.1.1-19sv
SonicWall Sma 500v Firmware=10.2.1.2-24sv
SonicWall Sma 500v

Event History

Dec 8, 2021
CVE Published
via MITRE·09:55 AM
Data Sourced
via MITRE·09:55 AM
DescriptionWeakness
Data Sourced
via NVD·10:15 AM
DescriptionSeverityWeaknessAffected Software
Jan 28, 2022
Known Exploited
via CISA·12:00 AM
Known Ransomware
via CISA·12:00 AM
Jul 16, 2025
News Published
via The Register·02:00 PM
News Published
via The Register·02:03 PM
News Published
via BleepingComputer·03:33 PM
News Published
via BleepingComputer·03:35 PM
Jul 24, 2025
News Published
via BleepingComputer·11:17 AM
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Frequently Asked Questions

1

What is the vulnerability ID for the SonicWall SMA 100 Appliances stack-based buffer overflow vulnerability?

The vulnerability ID for the SonicWall SMA 100 Appliances stack-based buffer overflow vulnerability is CVE-2021-20038.

2

What is the severity of CVE-2021-20038?

The severity of CVE-2021-20038 is critical with a CVSS score of 9.8.

3

Which SonicWall SMA 100 Appliances firmware versions are affected by CVE-2021-20038?

SonicWall SMA 200, 210, 400, 410, and 500v appliances firmware versions 10.2.0.8-37sv, 10.2.1.1-19sv, and 10.2.1.2-24sv are affected by CVE-2021-20038.

4

How can an attacker exploit CVE-2021-20038?

A remote unauthenticated attacker can exploit CVE-2021-20038 by exploiting a stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables, potentially executing code as a 'nobody' user on the affected appliance.

5

Are SonicWall SMA 200, 210, 400, 410, and 500v appliances vulnerable to CVE-2021-20038?

Yes, SonicWall SMA 200, 210, 400, 410, and 500v appliances are vulnerable to CVE-2021-20038 if they are running the affected firmware versions.

Contact

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