Recientemente, nuestro servidor (VPS CentOS6.5) comenzó a alojar un sitio WP que estaba, o se convirtió, en infectado (a través del complemento revslider) con algún tipo de troyano (probablemente remitente de correo no deseado, ya que terminamos en la lista de Spamhaus muy rápidamente)
El núcleo (pensamos) es un pequeño archivo agradable llamado system.php
enlace
Lo que parece ser activado por un encabezado WP infectado header.php enlace
Logró crear 4 trabajos cron y estamos muy interesados en lo que estaba haciendo. ¿Cómo puedo averiguarlo?
Editar:
Aquí está header.php
<?php 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?>
y aquí hay una parte de los comandos & codificación utilizada en system.php
(demasiado grande para publicar aquí en su totalidad, vea el pastebin)
@system("killall -9 ".basename("/usr/bin/host"));
$so32 = "\x7f\x45\x4c\x46\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x03\x00\x03\x00\x01\x00\x00\x00\x20\x0d\x00\x00\x34\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x34\x00\x20\x00\x03
¿Alguien reconoce el tipo de codificación, así que puedo decodificar e investigar más a mí mismo?
Edición 2:
descubrimos que system.php usa codificación hexadecimal (descodificada enlace )
TL; DR es un ELF . ¿Hay alguna forma de averiguar qué hace, además de ejecutarlo en un cuadro de prueba?