CVE-2021-20039

Published: Dec 8, 2021Updated: Sep 5, 2025 Sources: CVE List NVDCWE-78

8.8HIGH

NVD MITRE

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-78

Affected Products

SonicWall

commercial·US

SonicWall SMA100

Networking Infrastructure

sma 200 firmware

Networking Infrastructure

sma 210 firmware

Networking Infrastructure

sma 410 firmware

Networking Infrastructure

sma 400 firmware

Networking Infrastructure

sma 500v firmware

Networking Infrastructure

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Execution

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References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026

psirt.global.sonicwall.com

http://packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-Authenticated-Command-Injection.html

packetstormsecurity.com

https://attackerkb.com/topics/9szJhq46lw/cve-2021-20039/rapid7-analysis

attackerkb.com

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