Cyber Resilience

CVE-2020-37200

MediumPublic PoC

Published: 11 February 2026

Published
11 February 2026
Modified
17 February 2026
KEV Added
Patch
CVSS Score v4 4.6 CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0002 4.5th percentile
Risk Priority 9 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2020-37200 is a medium-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Nsasoft Netsharewatcher. Its CVSS base score is 4.6 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 4.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Deeper analysis

CVE-2020-37200 is a buffer overflow vulnerability (CWE-121) affecting NetShareWatcher version 1.5.8.0, located in the registration key input field. The flaw enables attackers to crash the application by supplying oversized input, such as a 1000-character payload pasted into the field.

The vulnerability carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), indicating it can be exploited remotely by unauthenticated attackers with low complexity and no user interaction. Successful exploitation results in a denial-of-service condition, causing high-impact availability disruption through application crashes without affecting confidentiality or integrity.

Advisories and proof-of-concept details are documented in references such as the Vulncheck advisory at https://www.vulncheck.com/advisories/netsharewatcher-key-denial-of-service and an Exploit-DB entry at https://www.exploit-db.com/exploits/47860, along with the vendor site at http://www.nsauditor.com/. No specific patches or mitigation steps are detailed in the provided information.

EU & UK References

Vulnerability details

NetShareWatcher 1.5.8.0 contains a buffer overflow vulnerability in the registration key input that allows attackers to crash the application by supplying oversized input. Attackers can generate a 1000-character payload and paste it into the registration key field to trigger an…

more

application crash.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

Buffer overflow enables remote exploitation of a public-facing app for availability impact via application crash (T1190 + T1499.004).

Confidence: MEDIUM · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2020-37201Same product: Nsasoft Netsharewatcher
CVE-2019-25340Same vendor: Nsasoft
CVE-2019-25434Same vendor: Nsasoft
CVE-2019-25336Same vendor: Nsasoft
CVE-2020-37119Same vendor: Nsasoft
CVE-2020-37205Same vendor: Nsasoft
CVE-2024-43661Shared CWE-121
CVE-2025-70249Shared CWE-121
CVE-2025-70744Shared CWE-121
CVE-2025-50662Shared CWE-121

Affected Assets

nsasoft
netsharewatcher
1.5.8.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Requires validation of input length, format, and type at the registration key entry point to reject oversized payloads and prevent buffer overflow crashes.

prevent

Implements memory protections like stack canaries and non-executable stacks to detect and block unauthorized memory access from buffer overflows in oversized registration key inputs.

prevent

Mandates timely remediation of identified flaws such as the buffer overflow in NetShareWatcher 1.5.8.0 through patching or software replacement to eliminate the vulnerability.

References