This task (pick up 3 shellcodes from Shell-Storm and use polymorphism to beat pattern matching) sounds really sophisticated but you will see it’s a very handy way for AV evasion for your shellcode. Check my github account for the files.

We have to pick three random shellcodes from shell-storm.

  1. /bin/sh
  2. /bin/sh -c “ping localhost”
  3. chmod 0777 /etc/shadow

Shell

Source

Just changed 0x68732f2f (“hs//”) & 0x6e69622f(“nib/”) into 0x68732f6e (“hs/n“)& 0x69622f2f (“ib//“) 😉

original code morphed code

Ping localhost

Source

Adding some slashes.

original code morphed code

Chmod shadow

Source

Little math to hide the well known hexcode for “adow” 😛

original code morphed code

Playing around with registers and thinking creatively was very funny.

 

This blog post has been created for completing the requirements of the SecurityTube Linux Assembly Expert certification:
http://securitytube-training.com/online-courses/securitytube-linux-assembly-expert/

Student ID: SLAE-1036