CVE-2021-20038

9.8 CRITICAL CISA KEV - Actively Exploited
Published: December 08, 2021 Modified: October 31, 2025
View on NVD

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/jbaines-r7/badblood
Source: PSIRT@sonicwall.com
Exploit Third Party Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026
Source: PSIRT@sonicwall.com
Vendor Advisory
https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-multiple-vulnerabilities-fixed-2/
Source: PSIRT@sonicwall.com
Exploit Third Party Advisory
https://github.com/jbaines-r7/badblood
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory
https://www.rapid7.com/blog/post/2022/01/11/cve-2021-20038-42-sonicwall-sma-100-multiple-vulnerabilities-fixed-2/
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20038
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
US Government Resource

7 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.8 / 10.0
EPSS (Exploit Probability)
94.3%
100th percentile
Exploitation Status
Actively Exploited
Remediation due: 2022-02-11

Weaknesses (CWE)

CWE-121 CWE-787

Affected Vendors

sonicwall

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