A malicious addition to a Facebook link

December 22nd, 2010 Vyacheslav Zakorzhevsky Posted in Industry News, Kaspersky No Comments »

In the last few days we have discovered that spam messages with malicious links are being sent via instant messenger services. It turns out that the mailings were carried out by the Zeroll IM worm. A bot generated various messages depending on the language of the recipient. Here are a few of them:

“Wie findest du das Foto?” “seen this?? 😀 %s” “This is the funniest photo ever!” “bekijk deze foto :D” “uita-te la aceasta fotografie :D”

Like lots of other similar incidents, the cybercriminals have made use of social engineering, asking users to look at pictures with alluring names. At the end of the message there is a link such as http://www.facebook.com/l.php?u=********.org/Jenny.jpg. As well as the link to the Jenny.jpg file the messages included similar links to Sexy.jpg.

The page that the http://www.facebook.com/l.php?u= link leads to is not actually malicious – it contains a warning from Facebook telling the user they are leaving the site.

Facebook warning

If you add a link to any random site after ‘l.php?u=’, then a window opens with a warning from Facebook. However, after the user clicks the ‘Continue’ button the link will direct the user to the corresponding site. This mechanism was used by the cybercriminals to make the link to the malicious site look more legitimate.

When the browser redirects to the page ********.org/Jenny.jpg it leads to the file PIC1274214241-JPG-www.facebook.com.exe which is then launched by unsuspecting users. Hereafter, the terms jenny.jpg and sexy.jpg refer to this executable file.

After analyzing jenny.jpg and sexy.jpg it turned out that they were typical downloaders, protected by packers and written in Visual Basic.

Fragment of the downloader code after the jenny.jpg file is unpacked in full

The downloaders’ job is typical for these types of program – download another malicious program to the infected computer. In this case, it’s the file srce.exe. So that the user doesn’t suspect anything, the downloaders also open the picture that was promised in the original spam message. The picture is downloaded from the Internet (the link can be seen in the screenshot).

So what is srce.exe? It’s a dropper + downloader whose outer shell is also written in Visual Basic. It downloads IM-Worm.Win32.XorBot.a which uses Yahoo Messenger to send out messages to users.

So what we have here is a link to a page on Facebook being used in instant messaging spam instead of a direct link to a malicious object. You could say that Facebook is being used a service along the lines of bit.ly: it allows links to be modified so that they are directed via the Facebook domain.

Zeroll is still actively sending out spam. The messages contain links to different files, but with similar names such as Girls.jpg and Marisella.jpg. And even though people already know they shouldn’t just click any old links, even if it was sent by someone on their contact list, it’s worth reminding everyone again. If nothing else, cybercriminals are creative, and the Zeroll spam once again confirms this.


Lab Matters: ROP Techniques in Exploit Kits

December 21st, 2010 Tim Posted in Industry News, Kaspersky No Comments »

In this edition of the Lab Matters webcast, Kaspersky Lab’s senior anti-malware researcher Kurt Baumgartner discusses the use of ROP (return-oriented programming) techniques in vulnerability exploit packs. Baumgartner talks about how exploit packs and infected web sites launch drive-by attacks and provides a glimpse at the obfuscation tricks used by cyber-criminals.


Twitter, Leaks and Spam

December 13th, 2010 Marco Posted in Industry News, Kaspersky No Comments »

It’s quite common to see attackers use hot topics on social networks to force users to click on malicious links. So what would be more interesting these days than using the term “Wikileaks”?

The following message arrived this weekend on one of my spam mail accounts. The subject “Wikileaks on Twitter!” caught my attention as I didn’t expect to see a spam mail with that keyword.

The design was cleverly done to trick users into thinking the mail was sent from Twitter. The Twitter logo is integrated and the text promises to be a service e-mail. All three links lead to the same “Canadian Health & Care” Website which is already known for Phishing/Web Forgery.


From Nuisance Viruses to Stuxnet: Talking Malware With Eugene Kaspersky

December 9th, 2010 Tim Posted in Industry News, Kaspersky No Comments »

In the newest edition of the Lab Matters webcast, founder and chief executive officer of Kaspersky Lab Eugene Kaspersky discusses the evolution of malware attacks — from nuisance e-mail worms to well-organized, for-profit cyber-criminals taking control of millions of computers.

In this Q&A with Ryan Naraine, Kaspersky talks about the different eras in malicious computer activity, from passive viruses to Internet worms to botnets and, now, a new era of cyber-warfare.