What it is
CVE-2021-20039 is a vulnerability affecting SonicWall SonicWall SMA100. Improper neutralization of special elements in the SMA100 management interface '/cgi-bin/viewcert' POST http method allows a remote authenticated...
Vulnerability report
CVE-2021-20039
SonicWall SMA100
SonicWall / SonicWall SMA100 · 9.0.0.11-31sv and earlier
- Severity
- CVSS 8.8 · High
- Confidence
- —
- Exploit status
- —
- EPSS
- —
- First observed
- —
- Last observed
- —
Decision summary
What security teams need to know first
Direct answers before the deeper technical record.
Is it exploited?
No. KEV Intelligence has not recorded active exploitation signals yet.
Who is affected?
SonicWall / SonicWall SMA100 9.0.0.11-31sv and earlier.
What should we do?
Track for updates. Assess relevance to your asset inventory and enrichment workflows.
Overview
SonicWall SMA100
Improper neutralization of special elements in the SMA100 management interface '/cgi-bin/viewcert' POST http method allows a remote authenticated attacker to inject arbitrary commands as a 'nobody' user.
This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.
Vendor
Product
Affected
Status
SonicWall
SonicWall SMA100
9.0.0.11-31sv and earlier
Affected
SonicWall
SonicWall SMA100
10.2.0.8-37sv and earlier
Affected
SonicWall
SonicWall SMA100
10.2.1.1-19sv and earlier
Affected
SonicWall
SonicWall SMA100
10.2.1.2-24sv and earlier
Affected
- Published
- 08 Dec 2021
- Exploited since
- —
- Attack vector
- Remote
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
CVE References
- psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026 psirt.global.sonicwall.com · CVE Record https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026
- packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-Authen... packetstormsecurity.com · CVE Record http://packetstormsecurity.com/files/165563/SonicWall-SMA-100-Series-...
Exploitation evidence
Exploitation evidence for this CVE
Catalogues and sources that list this CVE as a known exploited vulnerability, when available.
No exploitation evidence rows are recorded for this CVE yet.
Detection
Operational artifacts and observed signals
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Observed signals
- Request targets
- 0
- User-Agents
- 0
Raw values available in Pro and Enterprise.
Scanner coverage
Metasploit template detected 28 Apr 2025.
View Metasploit template (opens in new tab)Virtual patch status
No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →Scanner Artifacts
Scanner and exploit-framework references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Metasploit | https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/http/sonicwall_cve_2021_20039.rb | 28 Apr 2025 |
Risk and context
Severity, weaknesses, and research context
CVSS v3.1
8.8
High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
—
All CVSS Scores
CVSS v3.1
8.8
High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v2.0
9.0
High
AV:N/AC:L/Au:S/C:C/I:C/A:C
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
Timeline
From disclosure to observed exploitation
-
Metasploit module available
Exploit module available
-
Public PoC available
Public proof-of-concept code published
-
CVE published
Vulnerability disclosed publicly
-
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.
- 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-2021-20039
Free JSON includes basic KEV fields{
"cve_id": "CVE-2021-20039",
"confidence": null,
"cvss_score": 8.8,
"epss_score": null,
"exploit_status": {
"exploited_in_the_wild": false,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}