CVE-2021-20016
CriticalExploitedPublic exploitA 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.
Published Mar 9, 2023 · Updated Aug 12, 2026 · Also known as TR-21-0159, TR-21-0978
Key Facts
Patch immediately- CVE-2021-20016 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Sma 500v (Sonicwall), Sma 100 Firmware (Sonicwall), Sma 200 Firmware (Sonicwall) and 4 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Apr 29, 2021 and is known to be used in ransomware campaigns. Public exploit code is available.
- EPSS estimates a 40% probability of exploitation in the next 30 days.
- Fixed versions are available, including Sma 100 Firmware 10.2.0.5-d-29sv.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
40%
Higher than 98.6% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings, used by ransomware
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2021-20016 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 3, 2021 | Nov 17, 2021 | Known |
| Industry KEV feed | Apr 29, 2021 | Nov 17, 2021 | Known |
| CIRCL KEV | Nov 3, 2021 | Nov 17, 2021 | Known |
| ENISA EUVD | Nov 3, 2021 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
7 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Sma 500vSonicwall | See advisory | n/a |
| Sma 100 FirmwareSonicwall | See advisory | 10.2.0.5-d-29sv |
| Sma 200 FirmwareSonicwall | See advisory | n/a |
| Sma 210 FirmwareSonicwall | See advisory | n/a |
| Sma 400 FirmwareSonicwall | See advisory | n/a |
Patched Releases
Sma 100 Firmware
10.2.0.5-d-29sv
Timeline
Added to Industry KEV feed
Apr 29, 2021
Added to CISA KEV
Nov 3, 2021
Added to CIRCL KEV
Nov 3, 2021
Added to ENISA EUVD
Nov 3, 2021
Publicly disclosed
Mar 9, 2023
Last updated
Aug 12, 2026
Weakness Type
- CWE-89 Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
References
- advisoryhttps://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0001
- advisoryhttps://securityaffairs.co/
- advisoryhttps://securityaffairs.co/wordpress/114818/security/sonicwall-firmware-updates-sma-100.html?utm_source=rss&utm_medium=rss&utm_campaign=sonicwall-firmware-updates-sma-100
- advisoryhttps://securityaffairs.co/wordpress/114818/security/sonicwall-firmware-updates-sma-100.html?utm_source=rss&utm_medium=rss&utm_campaign=sonicwall-firmware-updates-sma-100SonicWall
- advisoryhttps://securityaffairs.co/wordpress/125400/security/sonicwall-sma-100-devices-flaws.html
FAQ
Common Questions.
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.
Affected: Sma 500v (Sonicwall); Sma 100 Firmware (Sonicwall); Sma 200 Firmware (Sonicwall), among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Apr 29, 2021 and is known to be used in ransomware campaigns.
Yes. It was added on Nov 3, 2021 with a federal remediation due date of Nov 17, 2021.
Public exploit code is available.
Fixed versions are available, including Sma 100 Firmware 10.2.0.5-d-29sv.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2021-20016 Running On Your Attack Surface?
Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.
Request A Demo