CVE-2020-37215: MSN Password Recovery DoS Vulnerability

CVE-2020-37215 Overview

CVE-2020-37215 is a denial of service vulnerability affecting MSN Password Recovery version 1.30. The vulnerability exists due to a classic buffer overflow condition (CWE-120) in the application's registration code handling mechanism. Attackers can crash the application by supplying an oversized input in the registration code field, specifically by generating a 9000-byte buffer of repeated characters and pasting it into the 'User Name and Registration Code' field.

Critical Impact

Successful exploitation allows attackers to cause a denial of service by crashing the MSN Password Recovery application through buffer overflow in the registration input field.

Affected Products

• MSN Password Recovery version 1.30

Discovery Timeline

• 2026-02-11 - CVE CVE-2020-37215 published to NVD
• 2026-02-12 - Last updated in NVD database

Technical Details for CVE-2020-37215

Vulnerability Analysis

This vulnerability is classified as CWE-120 (Buffer Copy without Checking Size of Input), commonly known as a classic buffer overflow. The MSN Password Recovery application fails to properly validate the length of user-supplied input in the registration code field before copying it to a fixed-size memory buffer. When a user or attacker supplies input exceeding the expected buffer size (approximately 9000 bytes of repeated characters), the application writes beyond the allocated memory boundaries, corrupting adjacent memory and causing the application to crash.

The local attack vector requires user interaction, as an attacker must either have direct access to the system running the vulnerable software or convince a user to paste malicious input into the registration field. While this vulnerability does not allow code execution based on current analysis, it demonstrates poor input validation practices that could potentially be leveraged for more severe attacks.

Root Cause

The root cause is insufficient input validation in the registration code processing function. The application allocates a fixed-size buffer for storing user registration data but does not verify that incoming data fits within the allocated space before performing the copy operation. This lack of boundary checking allows an attacker to overflow the buffer with an oversized input string.

Attack Vector

The attack requires local access to the vulnerable application and user interaction. An attacker constructs a payload consisting of approximately 9000 bytes of repeated characters and inputs this data into the 'User Name and Registration Code' field. When the application attempts to process this oversized input, the buffer overflow occurs, leading to memory corruption and an application crash.

The exploitation process involves:

1. Generating a buffer of approximately 9000 repeated characters (e.g., 'A' characters)
2. Accessing the MSN Password Recovery application's registration interface
3. Pasting the oversized buffer into the User Name and Registration Code field
4. Triggering the crash when the application attempts to process the input

For technical details on the exploitation technique, refer to the Exploit-DB #47839 advisory.

Detection Methods for CVE-2020-37215

Indicators of Compromise

• Presence of MSN Password Recovery version 1.30 installed on endpoints
• Application crash logs or Windows Error Reporting entries related to MSN Password Recovery
• Unexpected termination of the MSN Password Recovery process

Detection Strategies

• Monitor for application crashes involving MSN Password Recovery executables
• Implement endpoint detection rules to identify processes associated with vulnerable software versions
• Use SentinelOne's behavioral AI to detect anomalous application terminations indicative of exploitation attempts

Monitoring Recommendations

• Enable Windows Event Log monitoring for application crash events (Event ID 1000, 1001)
• Deploy endpoint inventory scanning to identify systems running MSN Password Recovery version 1.30
• Configure SentinelOne agents to alert on suspicious buffer overflow patterns in monitored applications

How to Mitigate CVE-2020-37215

Immediate Actions Required

• Uninstall MSN Password Recovery version 1.30 from all affected systems
• Consider alternative password recovery solutions that are actively maintained and patched
• If the software is business-critical, isolate systems running the vulnerable version until a patch or replacement is available
• Review the VulnCheck Advisory for additional guidance

Patch Information

No official vendor patch is currently available for this vulnerability. The vendor has not released an updated version addressing the buffer overflow condition. Organizations should consider discontinuing use of the affected software or implementing compensating controls.

Additional information about the vendor may be found at the Top Password website.

Workarounds

• Remove or disable MSN Password Recovery version 1.30 from production systems
• Restrict local access to systems where the vulnerable software must remain installed
• Implement application allowlisting to prevent unauthorized execution of the vulnerable application
• Train users to avoid pasting untrusted content into application input fields