CVE-2021-20035: SonicWall SMA100 Appliances OS Command Injection Vulnerability

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: yes — in CISA KEV since 2025-04-16
EPSS: 4.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-09-27 · updated 2026-06-17
Weakness: CWE-78

Description

Improper neutralization of special elements in the SMA100 management interface allows a remote authenticated attacker to inject arbitrary commands as a 'nobody' user which potentially leads to DoS.

Affected products

SonicWall Sma 200 Firmware: before 9.0.0.11-31sv; from 10.2.0.0 before 10.2.0.8-37sv; from 10.2.1.0 before 10.2.1.1-19sv — fixed in 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv
SonicWall Sma 210 Firmware: before 9.0.0.11-31sv; from 10.2.0.0 before 10.2.0.8-37sv; from 10.2.1.0 before 10.2.1.1-19sv — fixed in 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv
SonicWall Sma 400 Firmware: before 9.0.0.11-31sv; from 10.2.0.0 before 10.2.0.8-37sv; from 10.2.1.0 before 10.2.1.1-19sv — fixed in 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv
SonicWall Sma 410 Firmware: before 9.0.0.11-31sv; from 10.2.0.0 before 10.2.0.8-37sv; from 10.2.1.0 before 10.2.1.1-19sv — fixed in 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv
SonicWall Sma 500V: before 9.0.0.11-31sv; from 10.2.0.0 before 10.2.0.8-37sv; from 10.2.1.0 before 10.2.1.1-19sv — fixed in 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv

How to fix

Upgrade to a fixed version: SonicWall Sma 200 Firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv; SonicWall Sma 210 Firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv; SonicWall Sma 400 Firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv; SonicWall Sma 410 Firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv; SonicWall Sma 500V 10.2.0.8-37sv, 10.2.1.1-19sv, 9.0.0.11-31sv. Check the vendor advisory for mitigations.

References

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