Grey Noise has released a free online tool that allows users to quickly check whether their home or business IP address has been involved in malicious internet scanning.

As more residential networks are unknowingly pulled into cybercriminal infrastructure, the tool provides an accessible way for non-technical users to see if their IP has been misused. Called Grey Noise IP Check, the tool is the latest step in the company’s push to make threat intelligence more widely available.

Figure 1. IP Address.

Grey Noise, a U.S.-based security intelligence firm, specializes in tracking what it refers to as the internet’s “background noise”—the constant stream of automated scanning and probing activity targeting public networks. Its global sensor system monitors IP behavior and classifies it as harmless, compromised, or actively malicious. Figure 1 shows IP Address.

When a user visits the site, the tool analyzes their current IP address and returns one of three labels within seconds:

• Clean – No evidence of scanning or malicious behavior, typical for household connections.
• Suspicious/Malicious – Activity resembling brute-force attempts, vulnerability scans, or port probing.
• Known Business Service – The address belongs to a cloud provider, VPN, or enterprise network and isn’t inherently harmful.

If an IP falls into the second or third category, users also receive a 90-day activity timeline, including behavior tags such as SSH probing or web exploit attempts. Such activity may signal malware on a computer, a hacked router, or a compromised smart device.

GreyNoise notes that many households remain unaware when part of their network is hijacked for cyberattacks [1]. Devices may function normally while the IP silently participates in botnets or scanning campaigns—potentially causing emails to be blocked, services to deny access, or accounts to trigger security protections.

For advanced users, the company also provides a free, unauthenticated JSON-based API that can be queried with tools like curl, allowing easy integration into scripts, VPN checks, or device management workflows.

The tool offers a simple, non-intrusive way to assess whether a network may be compromised without deep configuration changes or antivirus scanning. GreyNoise recommends users periodically check their IP address, keep router firmware updated, replace default admin credentials, and use trusted DNS filtering for added protection.

Reference:

1. https://cyberinsider.com/free-scanner-reveals-if-your-ip-address-is-used-for-malicious-activity/

Cite this article:

Keerthana S (2025), Free Tool Lets Users Check Whether Their IP Address Has Been Linked to Malicious Activity, AnaTechMaz, pp.246