Look for the first GET request to that file. The source IP address is the attacker’s (though likely a VPN/proxy). Also look for POST requests after the GET – that shows what commands they ran.
The best defense is preventing the initial upload by hardening file upload forms and using file integrity monitoring to alert you if a new file suddenly appears in your directory. b374k.php
John's curiosity was piqued, and he quickly opened his laptop to investigate further. He navigated to the server and began to analyze the file. As he opened it, he realized that it was a PHP shell, a type of script that allowed an attacker to execute system commands remotely. Look for the first GET request to that file
