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CVE-2021-20038

Published: Dec 8, 2021Updated: Oct 31, 2025 Sources: CVE List NVD BDUCWE-121
9.8CRITICAL
NVD MITRE
EPSS Score
99.9%
Top 0.0%
CISA KEV
Active Exploitation
Since Jan 28, 2022
Exploits
2 Known
Remediation
Patch Available
Self-Check
Nuclei · OpenVAS

Description

A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-121CWE-787

Affected Products

SonicWall
commercial·US
SMA 100
Networking Infrastructure
SMA 200
Networking Infrastructure
SMA 210
Networking Infrastructure
SMA 400
Networking Infrastructure
SMA 410
Networking Infrastructure
SMA 500v
Networking Infrastructure
SonicWall SMA100
Networking Infrastructure
sma 200 firmware
Networking Infrastructure
Apache Software Foundation
oss-project·USaka apache foundation
HTTP ServerOn-premWeb App
Networking Infrastructure / load-balancer-proxy
and 4 more affected products View all →

Exploitability

CISA Known Exploited Vulnerability
Added to KEV:Jan 28, 2022
Remediation due:Feb 11, 2022
Ransomware:Known ransomware use

Required action: Apply updates per vendor instructions.

2 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://nvd.nist.gov/vuln/detail/CVE-2021-20038
nvd.nist.gov
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026
psirt.global.sonicwall.com
https://github.com/jbaines-r7/badblood
github.com
and 3 more references View all →

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