---
title: "CVE-2021-20035: SonicWall SMA100 Appliances OS Command Injection Vulnerability"
url: https://erroneo.us/security/cve/CVE-2021-20035/
description: "CVE-2021-20035 (SonicWall SMA100 Appliances): Exploited in the wild (CISA KEV). Improper neutralization of special elements in the SMA100 management…"
type: vulnerability-record
section: "Security Digest"
date_published: 2021-09-27
date_modified: 2025-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2021-20035"
kev: true
cvss: 6.5
epss: 0.04181
license: All rights reserved. Quote with attribution and a link.
---

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

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run SonicWall SMA100 Appliances. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2025-04-16, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2025-05-07 ; treat that as the outer limit, not the target.
- EPSS 4.2% , percentile 91: FIRST’s model estimates a 4.2% chance of exploitation activity in the next 30 days, higher than 91% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.

## What it is

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 (CVE record)

- SonicWall SMA100: 9.0.0.10-28sv and earlier, 10.2.0.7-34sv and earlier, 10.2.1.0-17sv and earlier

## Severity

- CISA-ADP CVSS 3.1: 6.5 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`

## Exploitation

- CISA KEV: added 2025-04-16; federal due date 2025-05-07. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 4.18% probability of exploitation activity in the next 30 days; percentile 91.

## Sources

- [Listed in CISA KEV notes (psirt.global.sonicwall.com)](https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0022)
- [CVE.org record CVE-2021-20035](https://www.cve.org/CVERecord?id=CVE-2021-20035)
- [NVD entry CVE-2021-20035](https://nvd.nist.gov/vuln/detail/CVE-2021-20035)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20035)

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Source page: https://erroneo.us/security/cve/CVE-2021-20035/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt