CVE-2020-37206 Overview
CVE-2020-37206 is a denial of service vulnerability in Nsasoft ShareAlarmPro, a network access control and share monitoring tool. The flaw resides in the application's registration key input field. An attacker with local access can paste a 1000-character buffer payload into the registration key field to crash the application. The issue is categorized under [CWE-120] Buffer Copy without Checking Size of Input. The vulnerability requires user interaction and only affects availability of the local application.
Critical Impact
A local attacker can crash ShareAlarmPro by submitting an oversized registration key, disrupting network share monitoring and access control functions until the application is restarted.
Affected Products
- Nsasoft ShareAlarmPro (all versions per vendor advisory)
- CPE: cpe:2.3:a:nsasoft:sharealarmpro:-:*:*:*:*:*:*:*
- Component: nsasoft:sharealarmpro
Discovery Timeline
- 2026-02-11 - CVE-2020-37206 published to the National Vulnerability Database (NVD)
- 2026-02-26 - Last updated in NVD database
Technical Details for CVE-2020-37206
Vulnerability Analysis
The vulnerability is a classic buffer-handling weakness in the licensing input routine of ShareAlarmPro. The application accepts user-supplied text in the registration key dialog but does not validate the size of the input before processing it. When the supplied data exceeds the expected key length, the program terminates abnormally. The defect is local in nature because the attacker must interact directly with the application user interface to paste the malformed input. Successful exploitation results in loss of availability for the running ShareAlarmPro process but does not affect confidentiality or integrity.
Root Cause
The root cause is improper restriction of operations within the bounds of a memory buffer [CWE-120]. The registration key handler copies input into a fixed-size buffer without verifying the source length. Supplying approximately 1000 characters overruns the buffer and triggers a crash. There is no evidence in the advisory that the condition leads to controlled code execution.
Attack Vector
Exploitation requires local access and active user interaction. An attacker, or a user tricked through social engineering, pastes a 1000-character string into the registration key field within the ShareAlarmPro interface. The application processes the oversized value and crashes. The attack does not require privileges, but it does require the application to be running and the registration dialog to be accessible. Public proof-of-concept material is referenced on Exploit-DB #47859 and the VulnCheck Advisory for ShareAlarmPro.
No verified code examples are available. The vulnerability is described in prose only. Refer to the linked advisories for technical demonstration details.
Detection Methods for CVE-2020-37206
Indicators of Compromise
- Unexpected termination or crash events for the ShareAlarmPro process in the Windows Application event log.
- Windows Error Reporting (WER) entries referencing ShareAlarmPro.exe with access violation or buffer-related fault codes.
- Presence of unusually long strings (≥1000 characters) in clipboard history or recent user input artifacts on a host running ShareAlarmPro.
Detection Strategies
- Monitor for repeated abnormal exits of ShareAlarmPro.exe followed by user-initiated restarts, which may indicate exploitation attempts.
- Correlate Application Error events (Event ID 1000) where the faulting module belongs to ShareAlarmPro with concurrent interactive user sessions.
- Track process lifecycle telemetry from endpoint agents for short-lived ShareAlarmPro sessions following clipboard paste activity.
Monitoring Recommendations
- Enable Windows Error Reporting collection and forward .wer artifacts to a central log store for analysis.
- Baseline normal runtime duration of ShareAlarmPro on monitored hosts and alert on outlier crash patterns.
- Audit which user accounts and workstations have ShareAlarmPro installed so detection content can be scoped accurately.
How to Mitigate CVE-2020-37206
Immediate Actions Required
- Restrict interactive access to systems running ShareAlarmPro to trusted administrators.
- Inventory all endpoints where ShareAlarmPro is installed using software asset management tooling.
- Train operators not to paste untrusted content into the application's registration dialog.
Patch Information
No vendor patch is referenced in the advisory data. Review the VulnCheck Advisory for ShareAlarmPro and the NSA Auditor Homepage for any updated builds. If the vendor releases a fixed version, apply it on all affected hosts and validate by submitting a long test string in a controlled environment.
Workarounds
- Avoid opening the registration key dialog except when entering a known-valid license string.
- Run ShareAlarmPro under a least-privileged Windows account to limit blast radius of a process crash.
- Consider replacing ShareAlarmPro with an alternative network share monitoring tool if continued availability is critical and no vendor fix is forthcoming.
- Apply Windows AppLocker or Software Restriction Policies to prevent execution on hosts that do not require the application.
# Configuration example: query installed ShareAlarmPro instances across Windows endpoints
Get-WmiObject -Class Win32_Product | Where-Object { $_.Name -like "*ShareAlarmPro*" } | Select-Object Name, Version, InstallLocation
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
