CVE-2020-37196: Dnss Domain Name Search DoS Vulnerability

CVE-2020-37196 Overview

CVE-2020-37196 is a denial of service vulnerability in Dnss Domain Name Search Software that allows attackers to crash the application by providing an oversized registration key. This buffer overflow vulnerability (CWE-120) can be triggered by generating a 1000-character buffer payload and pasting it into the registration key field, causing an immediate application crash.

Critical Impact
Local attackers can cause application denial of service by exploiting improper input validation in the registration key field, disrupting software availability.

Affected Products

Dnss Domain Name Search Software

Discovery Timeline

2026-02-11 - CVE CVE-2020-37196 published to NVD
2026-02-12 - Last updated in NVD database

Technical Details for CVE-2020-37196

Vulnerability Analysis

This vulnerability exists due to a classic buffer overflow condition (CWE-120: Buffer Copy without Checking Size of Input) in the registration key validation routine of Dnss Domain Name Search Software. The application fails to properly validate the length of user-supplied input before copying it into a fixed-size buffer, allowing attackers to trigger a denial of service condition.

The attack requires local access and user interaction, as the malicious payload must be manually pasted into the registration key field within the application's user interface. When the oversized input is processed, it overwrites adjacent memory locations, causing the application to crash.

Root Cause

The root cause is improper input validation and lack of boundary checking when handling the registration key field. The application allocates a fixed-size buffer for the registration key but does not verify that the input length falls within acceptable bounds before processing. When a 1000-character payload is provided, the buffer overflow corrupts stack or heap memory, leading to application termination.

Attack Vector

The attack vector is local, requiring an attacker to have access to the system where Dnss Domain Name Search Software is installed. The exploitation process involves:

Generating an oversized payload (approximately 1000 characters)
Opening the Dnss Domain Name Search Software application
Navigating to the registration key input field
Pasting the malicious payload into the field
The application crashes due to buffer overflow

This vulnerability has been documented in Exploit-DB #47856, which provides details on the exploitation technique. Additional information is available in the VulnCheck Advisory on DNS Issues.

Detection Methods for CVE-2020-37196

Indicators of Compromise

Unexpected crashes or termination of Dnss Domain Name Search Software
Application crash logs showing memory access violations or stack buffer overflows
Presence of unusually long strings in clipboard history or input fields

Detection Strategies

Monitor application event logs for crash events related to Dnss Domain Name Search Software
Implement endpoint detection rules to identify buffer overflow attack patterns
Deploy application whitelisting to control execution of vulnerable software versions

Monitoring Recommendations

Enable crash dump collection for forensic analysis of application failures
Configure endpoint protection to alert on repeated application crashes
Review system logs for signs of local exploitation attempts

How to Mitigate CVE-2020-37196

Immediate Actions Required

Check with the vendor (NSA Auditor Tool) for available security patches or updates
Restrict access to systems running the vulnerable software to trusted users only
Consider removing or disabling the software if it is not essential to operations
Implement application-level input validation where possible

Patch Information

No specific patch information is currently available from the vendor. Organizations should monitor the vendor website for security updates and apply patches as soon as they become available.

Workarounds

Limit local access to systems running Dnss Domain Name Search Software to authorized personnel only
Implement endpoint protection solutions that can detect and block buffer overflow attempts
Consider using alternative domain name search tools that do not have this vulnerability
Educate users about the risks of pasting untrusted content into application fields

bash

# Example: Restrict application access using file system permissions (Windows)
# Run as Administrator to limit who can execute the vulnerable application
icacls "C:\Program Files\Dnss\dnss.exe" /inheritance:r /grant:r Administrators:RX