# Front-end Input Validation
![[images/Pasted image 20260104191919.png]]
- [CRTL+SHIFT+E] to show dev tools or view with burp
- No HTTP request performed indicates front-end validation ![[images/Pasted image 20260104192112.png]]
- pattern match ![[images/Pasted image 20260104192159.png]]
# Bypassing Front-End Input Validation
- Start `burp`
- Create an input such as `127.0.0.1` that performs a successful HTTP request
- POST request performed ![[images/Pasted image 20260104192430.png]]
- [CRTL+R] to send to `repeater`
- Modify request to append a command ![[images/Pasted image 20260104192605.png]]
- We have working command injection ![[images/Pasted image 20260104192626.png]]