Following is the list and its respective links of port scanners which are hosted publicly and can be used by a Penetration Tester for Passive Reconnaissance (Passive recon is an attempt to gain information about targeted computers and networks without actively engaging with the systems).
- You Get Signal – https://www.yougetsignal.com/tools/open-ports/
- View DNS Info – https://viewdns.info/
- Namp Online Scanner – https://hackertarget.com/nmap-online-port-scanner/
- IP Fingerprints – https://www.ipfingerprints.com/portscan.php
- Port Checker – http://ping.eu/port-chk/
- Pentest Tools – https://pentest-tools.com/network-vulnerability-scanning/tcp-port-scanner-online-nmap
- Whatismyip Port Scanner – http://www.whatsmyip.org/port-scanner/
These scanners are specifically used and helpful during an engagement where the client wants to know the attack scenarios from the perspective of an unknown attacker.
Happy Hacking 😊