Port scan protection

Updated 7 months ago by Yana Shch

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Port scanning protection is available in the browser profile "Other" section.

You can enable "Port scanning protection" in browser profile settings, which will prevent websites from checking your system for open ports. You can also customize this setting by adding ports that websites can scan.

Even with this feature enabled, Nmap scanning will still be done on some fingerprint checkers like, although it is not utilized by websites as far as we know due to legal reasons.

In computer science, a port is a communication endpoint. When an application is running on the computer, it opens a port. This port acts as an address using which applications can interact with each other.

Here are a few examples:

  • TeamViewer opens the following ports: 80, 443 and 5938 (TCP)
  • RDP (Remote Desktop Protocol) opens this port: 3389 (TCP and UDP)
A port can be any number from 0 to 65535.

Websites that utilize local open port scanning through web sockets can see what ports are open in a particular computer, and as a result, understand what program our users are running. According to our research, Facebook, eBay, and Amazon are using this fingerprinting method.

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