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Questions tagged [port-scanning]

The act of scanning the ports on a remote computer in a systematic fashion.

The act of scanning the ports on a remote computer in a systematic fashion. By finding ports which are unsecured ("open") port scanning can be used to identify security vulnerabilities on a system. As such, it can be used as a tool both by systems administrators (to find and secure vulnerabilities on their systems), or by attackers (to find vulnerabilities to exploit).

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How to check Network port access and display useful message?

I was trying to check whether the port is opened or not using powershell like follows. (new-object Net.Sockets.TcpClient).Connect("10.45.23.109", 443) This method works , but the output is not user-friendly. It means if there are no errors then it…
Samselvaprabu
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Fastest way to scan ports with Java

I made a very simple port scanner, but it runs too slow, so I'm looking for a way to make it scan faster. Here is my code: public boolean portIsOpen(String ip, int port, int timeout) { try { Socket socket = new Socket(); …
Rohit Malish
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How to retrieve both TCP and UDP ports with Nmap?

I need to retrieve both TCP and UDP ports in the same scan with Nmap in the fastest way possible. I'll try to explain it better. If I use the most common command: nmap 192.168.1.1 It retrieves ONLY TCP ports and it is really fast. If I use the…
raz3r
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nmap warning: giving up on port because retransmission cap hit (2)

I am trying to scan a large set of domain names using nmap. I used the following command: Nmap -PN -p443 -sS -T5 -oX out.xml -iL in.csv I get the following warning: Warning: xx.xx.xx.xx giving up on port because retransmission cap hit (2). Why…
Wiliam A
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Making a Fast Port Scanner

So I'm making a port scanner in python... import socket ip = "External IP" s = socket.socket(2, 1) #socket.AF_INET, socket.SOCK_STREAM def porttry(ip, port): try: s.connect((ip, port)) return True except: return…
Shane
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How to make the process of scanning TCP ports faster?

I'm trying to asynchronously scan TCP ports. Since the open ports take just a few hundredths of milliseconds to complete they're fine, but when ports are closed I have to wait for the response. So what happens is that I run the app and almost right…
NewHelpNeeder
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Implementing all portscanning techniques in C# / Creating raw low level packets in C#

I am trying to write a port scanner in C#. I did some research on port scanning methods. If you are interested, these are the links I found useful: http://www.cs.wright.edu/~pmateti/InternetSecurity/Lectures/Probing/index.html ^PPT…
claws
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Nmap IP range specification

I need to specify specific IP range for Nmap scan, for example: 192.168.1.140 - 192.168.3.255 If I do it like: 192.168.1-3.140-255 IP addresses like 192.168.2.7,192.168.3.7 won't be scanned (only 140-255 in 4th actet).
user2463016
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Checking open UDP Port in C++

How can I check if a remote UDP port is open by using native C++? Since UDP is connection-less, calling connect() is not helpful. I cannot try binding it since it is not local. nmap cannot also indicate. (however netstat can find out, but I think it…
Mustafa
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UDP port scanning Java finds only 1 open UDP port

I have an assigment about port scanning. I am scanning UDP ports of some IP addresses in Java.In my program (assuming everything is OK) I can only find one open UDP port. In the other hands port scanning over "nmap" I get 4 open UDP ports. Can…
snvngrc
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Simple TCP scan with Go

I am learning to use Golang to develop hacking tools through Blackhat-Go and port scan scanme.nmap.org on Windows and Linux while doing TCP scanning.Here's my code package main import ( "fmt" "net" "sort" ) func worker(ports, result…
L2ksy0d
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C# How do I check USB Ports with USB Hub and used Controller?

I am currently trying to scan all USB Ports with their USB Hub (check if it is Root or not) and to which controller they are connectet. To make it more visible: USB Port1 (nothing plugged in) -> USB Hub1 | |-> Controller 1 USB…
Megajin
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PHP Port Scanning

This may be a duplicate post, BUT I've not seen any answer that correctly resolves this. I'm trying to find a php script that can correctly determine the state of a TCP or UDP port. I've tried several of the ones I've found online and they all…
Rocket
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Threaded Python port scanner

I am having issues with a port scanner I'm editing to use threads. This is the basics for the original code: for i in range(0, 2000): s = socket(AF_INET, SOCK_STREAM) result = s.connect_ex((TargetIP, i)) if(result == 0) : …
Amnite
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Whats the difference between -sS and -PS in nmap?

I was learning how to use nmap and i have gone through many documentations and tutorials but no where iam getting perfect information about what is the use of -sS and -PS. In general what is the differences between all -s 's and -P 's? Both are for…
Revanth Kumar
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