---
title: "CVE-2021-20039: SonicWall SMA100 vulnerability | CubePath"
description: "Improper neutralization of special elements in the SMA100 management interface '/cgi-bin/viewcert' POST http method allows a remote authenticated…"
language: en
source: https://cubepath.com/security/cve/CVE-2021-20039
---

# CVE-2021-20039: SonicWall SMA100 vulnerability | CubePath

## 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.

Official description from the CVE record, published by sonicwall. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-20039)

## Key data

### CVSS 3.1 High 8.8

Score published by CISA-ADP in the CVE record.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

| Metric                 | Value     | What it means                                                                       |
| ---------------------- | --------- | ----------------------------------------------------------------------------------- |
| Attack vector          | Network   | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity      | Low       | No special conditions are needed. The attack can be repeated at will.               |
| Privileges required    | Low       | A basic user account is needed.                                                     |
| User interaction       | None      | No action from any user is needed.                                                  |
| Scope                  | Unchanged | The impact stays within the vulnerable component.                                   |
| Confidentiality impact | High      | Serious or total effect on the secrecy of data.                                     |
| Integrity impact       | High      | Serious or total effect on the trustworthiness of data.                             |
| Availability impact    | High      | Serious or total effect on availability.                                            |

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at [first.org/cvss](https://www.first.org/cvss/) .

### EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score

0.78746 (78.7% probability)

Percentile

99.6%

Scores of

Nov 10, 2026

Model

v2026.06.15

### CISA assessment as of Aug 15, 2025

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.

Exploitation

Public proof of concept recorded by CISA

Automatable

no

Technical impact

total

### Weakness (CWE)

CWE catalog version 5.0.

CWE names: Copyright © 2006-2026, The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CWE license.

- [CWE-78](https://cwe.mitre.org/data/definitions/78.html) Improper Neutralization of Special Elements used in an OS Command

## Affected products

Products listed in the CVE record, as the CNA published them.

- SonicWall SMA100

  - affected: 9.0.0.11-31sv and earlier
  - affected: 10.2.0.8-37sv and earlier
  - affected: 10.2.1.1-19sv and earlier
  - affected: 10.2.1.2-24sv and earlier

## References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

- [psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026](https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026)
- [packetstormsecurity.com/files/165563/SonicWall-SMA-100-Seri…](http://packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-Authenticated-Command-Injection.html)

## Timeline

1. ID reserved Dec 17, 2020
2. Record published Dec 8, 2021
3. Record last updated Sep 5, 2025

## Look up another CVE

## About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.

[Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection)

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 20:05 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)