CVE-2021-20039

9.0

HIGH CVSS 2.0

Juniper SMA Arbitrary Command Injection Vulnerability

Description

Improper neutralization of special elements in the SMA100 management interface '/cgi-bin/viewcert' POST http method allows a remote authenticated attacker to inject arbitrary commands as a 'nobody' user. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.

INFO

Published Date :

Dec. 8, 2021, 10:15 a.m.

Last Modified :

Nov. 21, 2024, 5:45 a.m.

Remotely Exploit :

Yes !

Source :

[email protected]

Affected Products

The following products are affected by CVE-2021-20039 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID	Vendor	Product
1	Sonicwall	sma_210_firmware
2	Sonicwall	sma_410_firmware
3	Sonicwall	sma_500v_firmware
4	Sonicwall	sma_200_firmware
5	Sonicwall	sma_400_firmware
6	Sonicwall	sma_210
7	Sonicwall	sma_410
8	Sonicwall	sma_500v
9	Sonicwall	sma_200
10	Sonicwall	sma_400

: Total Affected Vendor : 1 | Products : 10

CVSS Scores

The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.

Score	Version	Severity	Vector	Exploitability Score	Impact Score	Source
	CVSS 2.0	HIGH				[email protected]
	CVSS 3.1	HIGH				[email protected]

Solution

This information is provided by the 3rd party feeds.

Upgrade to version 10.2.0.9-41sv or 10.2.1.3-27sv or later.

Public PoC/Exploit Available at Github

CVE-2021-20039 has a 2 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-20039.

URL	Resource
http://packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-Authenticated-Command-Injection.html	Exploit Third Party Advisory VDB Entry
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026	Vendor Advisory
http://packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-Authenticated-Command-Injection.html	Exploit Third Party Advisory VDB Entry
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026	Vendor Advisory

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-20039 is associated with the following CWEs:

CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-20039 weaknesses.

CAPEC-6: Argument Injection Argument Injection CAPEC-15: Command Delimiters Command Delimiters CAPEC-43: Exploiting Multiple Input Interpretation Layers Exploiting Multiple Input Interpretation Layers CAPEC-88: OS Command Injection OS Command Injection CAPEC-108: Command Line Execution through SQL Injection Command Line Execution through SQL Injection

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

H4lo/awesome-IoT-security-article

Collect some iot-related security articles, including vulnerability analysis, security conferences and papers, etc.

iot-security

Updated: 1 month ago

285 stars 29 fork 29 watcher

Born at : Dec. 6, 2022, 1:11 p.m. This repo has been linked 47 different CVEs too.

jbaines-r7/badblood

SonicWall SMA-100 Unauth RCE Exploit (CVE-2021-20038)

exploit rce cve-2021-20038

Python

Updated: 6 months, 2 weeks ago

95 stars 24 fork 24 watcher

Born at : Jan. 11, 2022, 2:25 a.m. This repo has been linked 2 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-20039 vulnerability anywhere in the article.

BleepingComputer

SonicWall urges admins to patch critical RCE flaw in SMA 100 devices

SonicWall urges customers to patch SMA 100 series appliances against a critical authenticated arbitrary file upload vulnerability that can let attackers gain remote code execution. The security flaw ( ...

Published Date: Jul 24, 2025 (1 month ago)

Ars Technica

Google finds custom backdoor being installed on SonicWall network devices

Researchers from the Google Threat Intelligence Group said that hackers are compromising SonicWall Secure Mobile Access (SMA) appliances, which sit at the edge of enterprise networks and manage and se ...