CVE-2020-37206: ShareAlarmPro DOS Vulnerability

CVE-2020-37206 Overview

ShareAlarmPro contains a denial of service vulnerability that allows attackers to crash the application by supplying an oversized registration key. This buffer overflow vulnerability (CWE-120) can be exploited when an attacker generates a 1000-character buffer payload and pastes it into the registration key field, causing the application to crash.

Critical Impact

Local attackers can cause application crashes and denial of service by exploiting improper input validation in the registration key field, disrupting network access control functionality.

Affected Products

• ShareAlarmPro (all versions)
• NSAuditor Network Security Auditor components

Discovery Timeline

• 2026-02-11 - CVE CVE-2020-37206 published to NVD
• 2026-02-12 - Last updated in NVD database

Technical Details for CVE-2020-37206

Vulnerability Analysis

This vulnerability represents a classic buffer overflow (CWE-120) condition in ShareAlarmPro's registration key validation routine. The application fails to properly validate the length of user-supplied input before copying it into a fixed-size buffer. When a user pastes an oversized registration key (approximately 1000 characters) into the registration field, the application attempts to process this input without adequate boundary checking, resulting in memory corruption and subsequent application crash.

The local attack vector requires user interaction, as an attacker must convince a user to paste the malicious payload or gain local access to the system. While this limits the attack surface compared to network-exploitable vulnerabilities, it still presents a risk in environments where ShareAlarmPro is used for network access control operations.

Root Cause

The root cause of this vulnerability is improper buffer size validation in the registration key input handler. The application allocates a fixed-size buffer to store the registration key but does not enforce length restrictions on the input data. This allows arbitrarily long input strings to overflow the allocated buffer space, corrupting adjacent memory and triggering an unhandled exception that crashes the application.

Attack Vector

The attack requires local access and user interaction. An attacker can exploit this vulnerability by crafting a malicious payload consisting of approximately 1000 or more characters and either pasting it directly into the registration key field or convincing a legitimate user to do so. The attack vector is straightforward: generate a buffer payload of sufficient length to overflow the input buffer.

The vulnerability can be triggered by pasting an oversized string (approximately 1000 characters) into the registration key field of ShareAlarmPro. When the application attempts to process this input, the buffer overflow occurs, causing the application to crash. Technical details and proof-of-concept information are available in the Exploit-DB #47859 entry.

Detection Methods for CVE-2020-37206

Indicators of Compromise

• ShareAlarmPro application crashes or unexpected termination events
• Windows Event Log entries showing application faults in ShareAlarmPro processes
• Presence of unusually long strings in clipboard data prior to application crash
• Memory dump files generated by ShareAlarmPro crash events

Detection Strategies

• Monitor for repeated ShareAlarmPro application crashes in Windows Event Logs
• Implement endpoint detection rules to identify buffer overflow patterns targeting ShareAlarmPro
• Deploy application whitelisting to prevent unauthorized access to ShareAlarmPro registration interfaces
• Use SentinelOne's behavioral AI to detect anomalous application termination patterns

Monitoring Recommendations

• Enable crash dump collection for ShareAlarmPro to analyze potential exploitation attempts
• Monitor Windows Application event logs for Event ID 1000 (Application Error) involving ShareAlarmPro
• Configure alerts for multiple application crashes within a short time window
• Review clipboard history for suspicious long character strings if clipboard monitoring is enabled

How to Mitigate CVE-2020-37206

Immediate Actions Required

• Restrict access to ShareAlarmPro registration functionality to authorized administrators only
• Implement input validation controls at the operating system level where possible
• Consider disabling registration functionality if not actively needed
• Monitor for application crashes and investigate any suspicious termination events

Patch Information

No vendor patch information is currently available for this vulnerability. Organizations using ShareAlarmPro should contact NSAuditor for updated software versions that address this buffer overflow condition. Additional information may be available through the VulnCheck Advisory on ShareAlarmPro.

Workarounds

• Limit local access to systems running ShareAlarmPro to trusted users only
• Implement application control policies to restrict who can interact with the registration interface
• Use endpoint protection solutions like SentinelOne to detect and prevent buffer overflow exploitation attempts
• Consider deploying alternative network access control solutions if a patched version is not available
• Educate users about the risks of pasting unknown content into application input fields

Since no patch is currently available, organizations should implement access restrictions and monitoring to reduce risk:

# Configuration example
# Restrict ShareAlarmPro access to administrators only
# Review Windows Event Logs for application crashes:
# Event Viewer > Windows Logs > Application
# Filter for Event ID 1000 with ShareAlarmPro as the faulting application