KEV Intelligence

Vulnerability report

Active exploitation observed Confirmed confidence In CISA KEV

CVE-2021-20016

SonicWall SMA100

SonicWall / SonicWall SMA100 · SMA100 build version 10.x

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Severity
CVSS 9.8 · Critical
Confidence
Confirmed
Exploit status
Observed in sensors
EPSS
37.0%
First observed
27 Jun 2026
Last observed
12 Aug 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2021-20016 is an unauthenticated vulnerability affecting SonicWall SonicWall SMA100. A SQL-Injection vulnerability in the SonicWall SSLVPN SMA100 product allows a remote unauthenticated attacker to perform SQL...

Is it exploited?

Yes. KEV Intelligence sensors observed exploitation attempts with confirmed confidence.

Who is affected?

SonicWall / SonicWall SMA100 sma100 build version 10.x.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

SonicWall SMA100

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.

Vendor Product Affected Status
SonicWall SonicWall SMA100 SMA100 build version 10.x Affected
Published
03 Feb 2021
Exploitation Reported
03 Nov 2021
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

cisa malware ransomware edge

CVE References

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 03 Nov 2021

Independent exploitation attestation added to the KEV Intelligence record.

Active exploitation observed

KEV Intelligence sensor

First observed 27 Jun 2026

First-party sensor telemetry confirms matching exploitation attempts.

Used in malware

CISA

Recorded 03 Nov 2021

Malware families have been linked to exploitation of this CVE.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

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Source Added
CISA First 2021-11-03 00:00 UTC
Tenable Blog 2026-07-15 17:14 UTC
KEV Intelligence 2026-07-23 11:02 UTC
CVE 2026-08-12 04:21 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

First-party evidence of exploitation activity

Aggregate observations show the scale, recency, and distribution of activity without overstating sparse data.

2

Attempts observed

2

Unique attacker IPs

2

Attacker countries

GB · US

2

Sensors observed

Exploitation attempts over the last 55 days

Daily events observed by KEV Intelligence sensors

Updated 19 Aug 2026

0
1
0
10
6
1
0
21
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
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0
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1
0
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0
0
26 Jun 7 Jul 18 Jul 29 Jul 19 Aug

First observed 27 Jun 2026 · Last observed 12 Aug 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
1
User-Agents
1

Raw values available in Pro and Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

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Risk and context

Severity, weaknesses, and research context

CVSS v3.1

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

EPSS

37.0%

Weaknesses

Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') CWE-89

Recent mention · Tenable Blog

CVE-2026-15409, CVE-2026-15410: SonicWall SMA 1000 zero-day vulnerabilities exploited in the wild

SonicWall patched two recently exploited zero-day vulnerabilities in its SMA 1000 Series secure remote access appliances which may have been chained for unauthenticated remote code execution.Key takeawaysCVE-2026-15409 and CVE-2026-15410 are a pair of exploited vulnerabilities...

Read full advisory

All CVSS Scores

CVSS v3.1 9.8 Critical

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

CVSS v2.0 7.5 High

AV:N/AC:L/Au:N/C:P/I:P/A:P

Timeline

From disclosure to observed exploitation

  1. KEV confirmed by CVE

    Exploitation attested by an external source

  2. KEV confirmed by Tenable Blog

    Exploitation attested by an external source

  3. Observed by KEV Intelligence sensors

    Evidence-backed exploitation signal

  4. Indicators of compromise added (23)

    Indicators of compromise recorded

  5. Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  6. First public exploitation report

    Exploit observed in malware

  7. CVE published

    Vulnerability disclosed publicly

  8. CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2021-20016

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2021-20016",
  "confidence": "Confirmed",
  "cvss_score": 9.8,
  "cvss_estimated": false,
  "epss_score": 0.36952,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 2, "sensors": 2 }
}

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