Is there a way to inject javascript code into a website and make changes to it without using extensions like tamperedmonkey?

[MeduzaXK]

Hello, I'm trying to inject a script into the victim's binance account where the amount of money he has in his balance will be changed and no matter if he updates the fake amount, it will still be there even if he logs out, i did it using tamperedmoneky but the victim knows about this trick, can you suggest me another way to do it without using extensions?

 

[menekees]

You could do it via an MITM proxy.
Will take time to setup such proxy, but after that it will be universal (after you import your root certificate to chrome/firefox)

 

[vei]

you can mirror the website and run the output through regex checks and change whatever it is you want. it's a common tactic in web2tor websites to change crypto addresses when displaying the content.

 

[crypt0]

can be done via reverse proxy also i guess

 

[0x43rypt0n]

Yes for browser such as firefox you need to hook PR_Read and parse the readed server buffer then you can inject the js code to the web page