CVE-2021-20038

CriticalCVSS 9.8/10Known exploited (CISA KEV)Last modified Jun 17, 2026

Description

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.

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-121 CWE-787

Affected software

Vendor	Product	Versions
SonicWall	SonicWall SMA100	10.2.0.8-37sv and earlier; 10.2.1.1-19sv and earlier; 10.2.1.2-24sv and earlier

References

https://github.com/jbaines-r7/badbloodExploit, Third Party Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026Vendor Advisory
https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-multiple-vulnerabilities-fixed-2/Exploit, Third Party Advisory
https://github.com/jbaines-r7/badbloodExploit, Third Party Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026Vendor Advisory
https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-multiple-vulnerabilities-fixed-2/Exploit, Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20038US Government Resource

Timeline

Published: Dec 8, 2021
Last modified: Jun 17, 2026
Added to CISA KEV: Jan 28, 2022
NVD status: Analyzed

Related CVEs from 2021

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