TTY treatment

TTY treatment is a technique used in reverse shells for being able to do Ctrl+Z to clear the screen, Ctrl+C without quitting the reverse shell and be able to access commands history with up and down keys.

Linux

These are the commands used in linux to treat the tty:

$ script /dev/null -c bash or $ python3 -c "import pty; pty.spawn('/bin/bash')": Used to start a bash shell.

Press Ctrl+Z keys to background the shell:

  bash-5.2$ ^Z
  zsh: suspended  nc -lvnp 443

❯ stty raw -echo; fg: Make the shell a tty and foreground the shell.
reset xterm: Reset the shell to show it cleaner.
$ export TERM=xterm: Set the terminal to xterm. This is used for being able to do Ctrl+L.
$ export SHELL=bash: Set the shell to bash for better performance
$ stty rows <rows> cols <cols>: Set rows and columns to adjust shell size to current terminal window size. To see your terminal window size, open a new full terminal window and execute stty size. The first number is the number of rows and the second number is the number columns. In my case, it outputs “50 184” so I need to execute stty rows 50 cols 184 in the reverse shell.

Now, it’s created a interactive reverse shell for better performance and management in the machine.

Gabriel blog

TTY treatment

Linux