CriticalCISA KEVExploited in the wildPublic exploit

SQL Injection in SonicWall Secure Remote Access (SRA)

IdentifiersCVE-2021-20028CWE-89· Improper Neutralization of Special…

CVE-2021-20028 is an improper neutralization of SQL commands (SQL injection) vulnerability affecting SonicWall Secure Remote Access (SRA) appliances. The provided content states that it impacts end-of-life SRA products running all 8.x firmware and version 9.0.0.9-26sv or earlier. The flaw allows attacker-controlled input to be incorporated into backend SQL queries without sufficient sanitization or parameterization, enabling unauthorized database query manipulation on vulnerable internet-exposed appliances.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

The vulnerability can be exploited remotely against exposed SonicWall SRA appliances and has been associated in the provided content with real-world ransomware intrusion activity, including campaigns deploying LockBit. Successful exploitation can enable unauthorized access to appliance data and functionality and may serve as an initial access vector for broader compromise of the target environment.

Mitigation

If you can’t patch tonight, do this now.

Where immediate replacement is not yet complete, reduce exposure by removing affected SRA appliances from direct internet exposure, restricting access to trusted source IP ranges, disabling unnecessary remote access paths, and closely monitoring for signs of exploitation. Because the content explicitly states no patches are available for affected end-of-life SRA appliances, mitigation should be treated only as temporary risk reduction until the devices are decommissioned.

Remediation

Patch, then assume compromise.

The provided content indicates these affected SonicWall SRA products are end-of-life and that no patches are available for CVE-2021-20028 on those appliances. The recommended remediation is to decommission and replace affected end-of-life SRA appliances with supported products or supported firmware/platforms not affected by this vulnerability.

PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType

SonicwallSma 210 Firmwareoperating_system

SonicwallSma 410 Firmwareoperating_system

SonicwallSma 500v Firmwareoperating_system

SonicwallSra 1600 Firmwareoperating_system

SonicwallSra 4600 Firmwareoperating_system

SonicwallSra Va Firmwareoperating_system

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

6 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

6 SOURCESView more in app

cyber security newsNews

Mar 2, 2026

Hackers Attacking SonicWall Firewalls from 4,000+ unique IP Addresses to Exploit Vulnerabilities

A vulnerability affecting SonicWall SRA appliances; the content states affected appliances are end-of-life and have no available patches, making decommissioning necessary.

greynoise blogNews

Feb 27, 2026

Active Reconnaissance Campaign Targets SonicWall Firewalls Through Commercial Proxy Infrastructure

A critical SonicWall vulnerability (CVSS 9.8) listed in CISA KEV. The content indicates limited triggering during the campaign and explicitly warns that end-of-life SonicWall SRA appliances affected by this CVE have no patches available, recommending decommissioning/disconnection.

medium lcamNews

Apr 7, 2023

Makop: The Toolkit of a Criminal Gang | by L M | Medium

A vulnerability affecting SonicWall SMA100 appliances that was referenced as part of an exploitation campaign on internet-exposed devices to deploy LockBit ransomware.

krebs on securityNews

Feb 14, 2022

Wazawaka Goes Waka Waka - Krebs on Security

A recently patched vulnerability affecting SonicWall VPN appliances for which working exploit code was publicly released, making it significant for intrusion and ransomware-related operations.

+1 more in the timeline

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.

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Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware4

Malware families riding this exploit, with evidence and IOCs.

Detection signatures2

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES

MITRE CVE

cve.org · CVE-2021-20028

NVD

nvd.nist.gov/vuln/detail/CVE-2021-20028

MITRE CWE · CWE-89

Improper Neutralization of Special Elements…

Vendor Advisory

psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0017

US Government Resource

cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20028