Remove First Line Injection

The crack injects all of PHP files in the first line with the form:

<?php ...../** INJECTED CODE  */ ?> <?php
// NORMAL LINES
...

Remove first line that get injected on all PHP files:

find ./ -iname '*.php' -exec  sed -i '1 s/<?php/\n&/2;s/<?php.*\n//' {} \;