Once a web server and its services have been compromised, it is important to ensure that secure access can be maintained. This is usually accomplished with the aid of a web shell–a small program that provides stealth backdoor access and allows the use of system commands to facilitate post-exploitation activities.
Kali comes with several web shells; here we will use a popular PHP web shell called Weevely. For other technologies attackers might use, refer to https://webshell.co/.
Weevely simulates a Telnet session and allows the tester or attacker to take advantage of more than 30 modules for post-exploitation tasks, including the following:
- Browsing the target filesystem
- File transfer to and from the compromised systems
- Performing audits for common server misconfigurations
- Brute-forcing SQL accounts through the target system
- Spawning reverse...