Questions tagged [netcat]
Netcat is a computer networking service for reading from and writing network connections using TCP or UDP
293
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How to pass a bash variable (list of numeric data) to gnuplot *without using a file*
I am using netcat to get a series of points which I would like to plot with gnuplot. However, I am having trouble passing the data to gnuplot without writing it to a file first.
In the simplest case, ...
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netcat redirects stderr to stdout then variable losing newlines [duplicate]
I am working on a script to parse a file containing a list of IP addresses and ports then do a bunch of test on the ports with netcat. The port argument can be a single port, a list of ports, or a ...
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MD5 Hash modified trought netcat
I used dd to create a sample empty file with 1MB, edited the sample file, created a MD5 hash of the file, started a listener on the examiner machine, piped the output off to nc and compared the hashes....
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Can I relay the data received from Netcat to a URL as a POST?
I have a PHP-based website, and I'm trying to integrate it with another system.
This system sends XML data to a specific port (let's say port 9999). I am able to capture the incoming data and save it ...
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send (alsa) audio via network via UDP
This to my understanding records mono in wav format for 300 seconds to a named pipe called "mic_rec"
rec arecord -D hw:4,0 -d 300 -f cd -t wav -c 1 mic_rec
And this sends whatever it finds ...
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1
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Discrepancies in netcat installation process between debian bullseye vs debian bookworm-slim
In debian:bullseye
oot@4770c7ba00ac:/# apt install -y netcat
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be ...
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Netcat uploads hanging after a certain point
I'm working through an introductory cybersec challenge that requires me to upload a word and brute force a 4 digit code to a port. I put the combinations in a file, and tried to use netcat to upload ...
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How to pipe terminal interaction with running process over network?
How can I run a program that expects to be executing in a terminal in such a way that it's STDIO can be arbitrarily connected-to remotely?
Specifically, I want to be able to launch gdb on one host and ...
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Curl multipart request as raw using netcat
I user Copy as Url and got
curl URL
-H 'Accept: */*' \
-H 'Accept-Language: en-GB,en-US;q=0.9,en;q=0.8' \
-H 'Connection: keep-alive' \
-H 'Content-Type: multipart/form-data; boundary=----...
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1
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461
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Can i trust echo result of nc command for UDP?
Context :
I want to test UDP port with nc command
What happens :
nc command return nothing on output and 0 when i put echo $?
Which command :
nc -vzu <ip> <port>
echo $?
What is the ...
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1
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ipv6 multicast fails when it should loop back to self
So far I use multicast with ipv4 and it works; all involved computers run linux. I listen on two machines and send on one of those two (in a separate terminal). In the below example 'Hello 1' is ...
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1
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455
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Usage of named pipe as data source for netcat
I want to use netcat as a TCP-server that reads data from a named pipe. For that I did the following:
Step 1. Created a pipe and the server that uses it as a source
mkfifo /tmp/all.pipe
nc -k -l 8080 &...
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1
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netcat forwarding and listening
I am listening on a port for logs coming from a device, then I used netcat to redirect those logs to a text file whenever a log is available on the device and all this to happen in the background ...
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1
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71
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Unable to get output from netconsole
nc -l -u 6666 on the receiving machine gets no messages from netconsole.
tested by doing "echo test > /dev/kmsg"
i am able to connect with netcat by doing "nc -u 10.0.0.192 6666"...
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45
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finger daemon / nc fowarding error
For an assignment I'm trying to properly send a buffer overflow exploit with ncat in order gain root access on a vulnerable machine set up by the professor. I feel I created my egg right but I keep ...
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110
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How can I write a command into a subprocess?
Currently, I am working on a project where I use telnet to netcat to send an email message within my university.
I am trying to make the process automated but my script can't seem to enter in any ...
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1
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717
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Socat specify source port
How do I specify source port in socat?
In netcat I can simply:
nc -u -s 192.168.0.1 -p 8888 192.168.0.2 9999
I tried
socat udp4:192.168.0.2:9999 STDIN:192.168.0.1:8888
It's failed
STDIN: wrong ...
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0
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23
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why does Netcat show output in the wrong order?
I am using netcat to run a file over a network like so
nc -lvnp 1111 -e file
on the client machine, the connection is empty and I only get an output after I enter an input.
How to show the output of ...
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1
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191
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How do I inject a header line into a pipe via a shell script?
I am working on a process to send data via a pipe from one server to another for processing.
Although this is not the exact command, it might look something like this:
tail -f logfile | grep "abc&...
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How to port forward my ubuntu 22.04 using iptables
Do you know how to gives iptables rules to my machine in order to allow trafic from my public interfaces(wlp3s0) to my private interfaces(lo). Kinda with this topology: 192.168.1.1:80 => 127.0.0.1:...
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Bash script to open a port when traffice is being recieved
I have 2 Ubuntu boxes one of them acting as an Attack platform (we will call it AP), the other as an already compromised server (we will call it S1).
I have this rule
sudo iptables -t nat -I ...
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1
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270
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Is it possible to create a ncat loop?
If you had two computers, wanting to control one from another using only ncat, without using telnet, ssh or other networking tools and only two shells, how could i go about that?
I have successfully ...
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1
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3k
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"Connection refused" when I try to send a UDP packet with netcat on an embedded-linux board
I'm trying to send a binary packet to a local process, via netcat (nc), like this:
nc -w 1 -u localhost 10000 < my_binary_packet.bin
The output is:
read(net): Connection refused
Anyone know what'...
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netcat command not working
Any idea why nc command is not working and telnet is working.
Ideally nc will also work. I am trying to use nc in script but getting error however telnet is working. Ideally nc command is working for ...
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0
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293
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How to pass IP address to netcat as variable in bash scripting?
I have this script on a Linux machine that loops through a .txt file to see if connection is successful or not. When I give the IP directly is works. However, when I pass the variable it says: nc: ...
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0
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238
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Exporting Python's script errors/traceback to file with netcat
I have a Python script accessible with netcat: nc 'serverIP' port.
The Python script awaits an input from the user. If the input is expected, the script keeps running. If the input is unexpect (e.g. ...
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1
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871
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How can I connect to a specfic Ethernet interface using netcat
I am trying to use netcat to echo some data to a custom board I have. The board is connected using a 10G Ethernet connection. I can see that the link is up but when I try using netcat I am not getting ...
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511
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Basic webserver supporting post+get (using curl and netcat)
Sorry if the question's title isn't clear about the objective of this question.
I was able to make a respond-only webserver using Bash only; when it gets a curl post request, it returns results no ...
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2
answers
521
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netcat in systemd service resets
I am using netcat to connect to a server over TCP and continuously pipe the data received to file.
nc 10.0.2.2 3456 > file.data
When running this from terminal or a script it stays connected
I want ...
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930
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nc -lvnp (port) Non-responsive w/ PHP Reverse Shell til closed
I am currently working on Machine's on HackTheBox. I've used nc -lvnp (port) quite a bit and i've never ran into this issue:
$nc -lvnp 4444
listening on [any] 4444 ....
connect to [my IP] from (...
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1
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2k
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SOCAT (only) reverse tunnel
I have a situation where we are trying to get data from one network to another - specifically access to a private maven repo on a different network.
Network 1 contains a maven repo. And network is ...
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'netcat' not working as expected on Arch, but works on openSUSE Tumbleweed? What's going on?
I'm having a bit of trouble utilising netcat on Arch, specifically, the GNU version of it.
My situation: I basically made a simple server in Python that can accept multiple clients and send responses. ...
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3k
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netcat on ubuntu/kali-linux not working
I have a problem with netcat.I tried the "pickle rick" challenge on tryhackme,The problem is that I don't get a shell with netcat:
nc -lnvp 9999
and this is the output:
Listening on 0.0.0.0 ...
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1
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How to "talk" to a "parent" IP in a subnet?
I have access to just *nix systems. Either NetBSD and/or bare Linux-based OS.
So my question comes from the fact that ADB is not widely available on all platforms, if so is very hard to install or ...
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1
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netcat closing connection on localhost listening end after connection attempt
Ι am nc-listening on localhost:2500
▶ nc -l 2500
_
On another terminal I am trying to connect to this listening end
▶ nc -zv localhost 2500
nc: connectx to localhost port 2500 (tcp) failed: ...
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1
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netcat broadcast understanding
I'm using macOS with gnu netcat. I want to understand how can I broadcast message using netcat.
I have a netcat listening on 4555
netcat -l -p 4555 192.168.0.101
but as I attempt to send a broadcast ...
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1
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Using netcat to setup a bind shell on localhost, but having issue with '-e' flag
I'm trying to do a simple exercise, where I need to set up a "server" hosting a bind shell, using netcat. On my localhost.
I'm running ubuntu 20.04
I'm following this tutorial, that has this ...
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2
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2k
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'ncat' considers redirection as (additional) port specification when run from python script
In a python script I am trying to run a subrocess that listens and recives a file using ncat:
proc = subprocess.Popen(command,stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
...
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Playing, recording, and streaming sound with cat and /dev/dsp
A couple of comments on Hacker News suggest that, on FreeBSD, you can:
use cat to send a file ( a .wav file for instance ) to the audio
speaker (/dev/dsp).
record from the mic using a similar method.
...
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1
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2k
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Netcat with device or interface flag?
Traceroute has an -i flag,
-i interface, --interface=interface Specifies the interface through which traceroute should send packets. By default, the interface is selected according to the routing ...
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182
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How to get grep to exit immediately when command is received from netcat?
I want to open a port and listen for a command, and when that command comes in, immediately run a script.
The best I've come up with is (the echo is a substitute for my script):
nc -lk 9999 | grep -q ...
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2
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1
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963
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netcat producing EINVAL when sending to UDP IPv6 multicast
I'm using netcat on Fedora to test an IPv6 UDP multi-cast address. The command is
echo hi | nc -6 -u ff02::777:777:777 7777
netcat responds, "Invalid argument."
Running strace yields
...
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180
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Prevent ncat from terminating after running python script
How do I prevent ncat from terminating after running a python script? My current netcat command is: ncat -lvp 50000 -e main.py. I would also like it so there can only be one connection per ip.
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907
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netcat / nc / telnet perform math on received data then output
I am not an expert on bash so sorry in advance. For my high school CTF competition, I have to read in 3 numbers, perform some arithmetic on them, then output the value back to the server.
In ...
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0
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1k
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Netcat listener: Line break between syslog messages
I am playing with netcat command. On this linux system, I have set up a netcat listener on UDP 514, so that I get to see syslog messages from remote systems.
$ sudo nc -v -ulp 514
listening on [::]:...
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Can I delay exection or otherwise postpone an outgoing netcat connection within a pipe?
I'm not sure if this is an XY problem, but I have to aupport a horrible piece of software that won't talk to modern mail servers properly. It can only do SMTP and insists on providing AUTH ... even ...
- 1,253
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1
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270
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how to exit in bash script from ProFTPD via netcat after some copy operations
I am connecting to a proftpd server via netcat
nc 10.10.239.150 21
Then I am doing some copy operations like
"The mod_copy module implements SITE CPFR and SITE CPTO commands"
After "...
- 101
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1
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709
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Netcat working on Linux but not on mac terminal
When I run
nc -l 2399
on my mac it doesn't work, regardless of what device I'm trying to connect to on. I run
nc 192.168.1.24 2399
and it just prompts me for the next input.
When I start the listen ...
1
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1
answer
451
views
Get my public IP from ifconfig.co using netcat
From my Android TV box, I would like to get my public IP and other related info from ifconfig.co, but it does not seem to work. If I try this code, it works fine:
adb -s 192.168.1.125:5555 shell ...
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3k
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How to "cat" a socket?
So to read and write to a socket:
Write to a socket:
echo "hello" > /dev/tcp/192.168.0.144/27002
Read from socket:
netcat -p 27002 -l
BUT... I would like to read a socket using "...
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