CVE-2020-37200: Nsasoft NetShareWatcher stack buffer overflow in registration key input

Executive brief

NetShareWatcher, a tool used for monitoring network shares, contains a flaw in how it handles license registration keys. An attacker can cause the software to crash by entering an excessively long string of characters into the registration field. This results in a denial of service, preventing legitimate users from using the application.

Technical details

A stack-based buffer overflow (CWE-121) exists in NetShareWatcher version 1.5.8.0. The vulnerability is located in the registration key input component, which fails to properly validate the length of the input string. An attacker can trigger the overflow by providing a payload of approximately 1,000 characters into the 'Key' field. While the primary impact is a denial of service (application crash), stack-based overflows can sometimes be leveraged for arbitrary code execution depending on system protections. The exploit requires local interaction to paste the malicious string into the registration interface.

Affected products

• Nsasoft (Nsauditor) NetShareWatcher 1.5.8.0

Timeline

• 2020-01-06: disclosed: Initial PoC exploit published on Exploit-DB
• 2026-02-11: advisory: NVD publication and CVE assignment

References

• http://www.nsauditor.com/
• https://www.exploit-db.com/exploits/47860
• https://www.vulncheck.com/advisories/netsharewatcher-key-denial-of-service