Portscanner

[Supervisor]

A port scanner is a software application designed to probe a server or host for open ports. This is often used by administrators to verify security policies of their networks and by attackers to identify running services on a host with the view to compromise it.

A port scan or portscan can be defined as a process that sends client requests to a range of server port addresses on a host, with the goal of finding an active port. While not a nefarious process in and of itself, it is one used by hackers to probe target machine services with the aim of exploiting a known vulnerability of that service, however the majority of uses of a port scan are not attacks and are simple probes to determine services available on a remote machine. Source (Wikipedia)

Spoiler: List

Nmap
Zenmap
Lama Portscanner (german)

I'm sure there are better ones. Post your favorite one below! We've got to find the best one

 

[L.]

LaMa

 

[ehthe]

Nmap

 

[User_418]

Nmap

 

[Bluscream]

Zenmap

 

[9dc]

nmap

 

[Next]

NextScan (is my personal service, i will put online shortly)

 

[r00t-Server]

nmap is very Easy and thank you

 

[YeiBack]

NMap

 

[Qraktzyl]

I love port scanning, sometimes I try to find several ips where there is a teamspeak server query port listening, and try my ip stresser against it. It is very fun.

nmap --open -v -p 10011 192.168.1.*

 

[Asphyxia]

I like Network Mapper (Nmap) and Angry IP Scanner.

 

[swarmdeco]

Hey! My favorite is nmap (but I usually use Zenmap for screenshot/evidence reporting).

Something important about reconnaissance is that you has to be as stealthy as fuck, it means you cannot alert the targeted company/infrastructure security systems (WAF/IDS/IPS/That-fat-daily-log-reader-guy-that-noone-has). Nmap is a great tool but a powerful weapon as well, so in order to NOT GO full retard here are some quick tips:

• nmap -sS <host>: That argument means stealth-scan (sS).
• sS will do half-tcp connections (SYN-SYN/ACK-RST) - Study the TCP-Three way handshake! It's useful (no it's not but I don't encourage SC haha)
• This method will only list open ports, not what's running on them. Nmap will do it's best to match with a known-port-database.

If you want to know what is running on a specific port run nmap -sCV -p <port> <host>, that'll do a full TCP connection (SYN-SYN/ACK-ACK) and get the banner.

Regards,
- Swarm.

* Just to mention it (and avoid SC confusion) Zenmap is just a GUI for nmap.