VDB-187742 · CVE-2021-20038 · SNWLID-2021-0026

SonicWALL SMA100/SMA 200/SMA 210/SMA 400/SMA 410 mod_cgi module stack-based overflow

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.5	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in SonicWALL SMA100, SMA 200, SMA 210, SMA 400 and SMA 410. Impacted is an unknown function of the component mod_cgi module. Such manipulation leads to stack-based overflow. This vulnerability is uniquely identified as CVE-2021-20038. The attack can be launched remotely. Moreover, an exploit is present.

Detailsinfo

A vulnerability, which was classified as critical, has been found in SonicWALL SMA100, SMA 200, SMA 210, SMA 400 and SMA 410 (Firewall Software). Affected by this issue is some unknown functionality of the component mod_cgi module. The manipulation with an unknown input leads to a stack-based overflow vulnerability. Using CWE to declare the problem leads to CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). Impacted is confidentiality, integrity, and availability.

The weakness was disclosed 12/08/2021 as SNWLID-2021-0026. The advisory is available at psirt.global.sonicwall.com. This vulnerability is handled as CVE-2021-20038 since 12/17/2020. Technical details are unknown but an exploit is available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 03/14/2025).

It is declared as attacked. This issue was added on 01/28/2022 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 02/11/2022:

Apply updates per vendor instructions.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

Firewall Software

Vendor

SonicWALL

Name

License

commercial

Website

Vendor: https://www.sonicwall.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/17/2020 🔍
12/08/2021 +356 days 🔍
12/08/2021 +0 days 🔍
03/14/2025 +1192 days 🔍

Sourcesinfo

Vendor: sonicwall.com

Advisory: SNWLID-2021-0026
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-20038 (🔍)
GCVE (CVE): GCVE-0-2021-20038
GCVE (VulDB): GCVE-100-187742
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 12/08/2021 13:02
Updated: 03/14/2025 18:23
Changes: 12/08/2021 13:02 (38), 12/11/2021 06:53 (2), 12/11/2021 07:03 (1), 04/22/2024 18:19 (26), 09/17/2024 17:21 (1), 03/14/2025 18:23 (19)
Complete: 🔍
Cache ID: 216::103