CVE-2021-20028
CriticalExploitedPublic exploitImproper neutralization of a SQL Command leading to SQL Injection vulnerability impacting end-of-life Secure Remote Access (SRA) products, specifically the SRA appliances running all 8.x firmware and 9.0.0.9-26sv or earlier
Published Mar 9, 2023 · Updated Oct 21, 2025
Key Facts
Patch immediately- CVE-2021-20028 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Sma 210 Firmware (Sonicwall), Sma 410 Firmware (Sonicwall), Sma 500v Firmware (Sonicwall) and 4 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Jun 8, 2021 and is known to be used in ransomware campaigns. Public exploit code is available.
- EPSS estimates a 30% probability of exploitation in the next 30 days.
- Fixed versions are available, including Sma 210 Firmware 9.0.0.10-28sv, Sma 410 Firmware 9.0.0.10-28sv, Sma 500v Firmware 9.0.0.10-28sv.
- 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)
30%
Higher than 98.2% 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-2021-20028 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
Improper neutralization of a SQL Command leading to SQL Injection vulnerability impacting end-of-life Secure Remote Access (SRA) products, specifically the SRA appliances running all 8.x firmware and 9.0.0.9-26sv or earlier
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Mar 28, 2022 | Apr 18, 2022 | Known |
| Industry KEV feed | Jun 8, 2021 | Apr 18, 2022 | Known |
| CIRCL KEV | Mar 28, 2022 | Apr 18, 2022 | Known |
| ENISA EUVD | Mar 28, 2022 | n/a | Not reported |
Required action: The impacted product is end-of-life and should be disconnected if still in use.
Affected Products
7 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Sma 210 FirmwareSonicwall | See advisory | 9.0.0.10-28sv |
| Sma 410 FirmwareSonicwall | See advisory | 9.0.0.10-28sv |
| Sma 500v FirmwareSonicwall | See advisory | 9.0.0.10-28sv |
| Sra 1600 FirmwareSonicwall | See advisory | 9.0.0.10-28sv |
| Sra 4600 FirmwareSonicwall | See advisory | 9.0.0.10-28sv |
Patched Releases
Sma 210 Firmware
9.0.0.10-28sv
Sma 410 Firmware
9.0.0.10-28sv
Sma 500v Firmware
9.0.0.10-28sv
Sra 1600 Firmware
9.0.0.10-28sv
Sra 4600 Firmware
9.0.0.10-28sv
Sra Va Firmware
9.0.0.10-28sv
Timeline
Added to Industry KEV feed
Jun 8, 2021
Added to CISA KEV
Mar 28, 2022
Added to CIRCL KEV
Mar 28, 2022
Added to ENISA EUVD
Mar 28, 2022
Publicly disclosed
Mar 9, 2023
Last updated
Oct 21, 2025
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-2021-0017
- advisoryhttps://www.itsecuritynews.info/suspected-chinese-cyber-spies-target-unpatched-sonicwall-devices/
- advisoryhttps://www.theregister.com/2021/07/15/sonicwall_secure_access/
- advisoryVulnCheck exploitation report
- advisoryUSOM advisory
FAQ
Common Questions.
Improper neutralization of a SQL Command leading to SQL Injection vulnerability impacting end-of-life Secure Remote Access (SRA) products, specifically the SRA appliances running all 8.x firmware and 9.0.0.9-26sv or earlier
Affected: Sma 210 Firmware (Sonicwall); Sma 410 Firmware (Sonicwall); Sma 500v 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 Jun 8, 2021 and is known to be used in ransomware campaigns.
Yes. It was added on Mar 28, 2022 with a federal remediation due date of Apr 18, 2022.
Public exploit code is available.
Fixed versions are available, including Sma 210 Firmware 9.0.0.10-28sv, Sma 410 Firmware 9.0.0.10-28sv, Sma 500v Firmware 9.0.0.10-28sv.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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