CVE-2021-20016

Name: CVE-2021-20016
Creator: NVD / NIST
Published: 2021-02-04T06:15:13.817+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10Actively ExploitedEPSS 40.04%

Last modified Jun 17, 2026

CVE-2021-20016 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. A SQL-Injection vulnerability in the SonicWall SSLVPN SMA100 product allows a remote unauthenticated attacker to perform SQL query to access username password and other session related information. This vulnerability impacts SMA100 build version 10.x.. CISA has confirmed active exploitation in the wild. EPSS estimates a 40.04% chance of exploitation in the next 30 days.

Description

A SQL-Injection vulnerability in the SonicWall SSLVPN SMA100 product allows a remote unauthenticated attacker to perform SQL query to access username password and other session related information. This vulnerability impacts SMA100 build version 10.x.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

40.04%

98.4th percentile

Probability of exploitation in the next 30 days. Learn more

Exploitation Status

This vulnerability is listed in CISA’s Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. Federal agencies must remediate by Nov 17, 2021.

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Sonicwall	Sma 100 Firmware	>= 10.0.0.0, < 10.2.0.5-d-29sv
Sonicwall	Sma 200 Firmware	All versions
Sonicwall	Sma 210 Firmware	All versions
Sonicwall	Sma 400 Firmware	All versions
Sonicwall	Sma 410 Firmware	All versions
Sonicwall	Sma 500v	All versions

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0001Mitigation, Vendor Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0001Mitigation, Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20016US Government Resource

Timeline

Published: Feb 4, 2021
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2021-20016?

How severe is CVE-2021-20016?

CVE-2021-20016 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 40.04% probability of exploitation in the next 30 days. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog.

How do I fix CVE-2021-20016?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20016?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST