When is a picture not worth 1000 words?

When it is not actually a picture but an obfuscated malicious VB script! That’s the story with W32/VBSAuto-F — yet another autorun worm that sets a number of self-starting registry entries, spreads via USB drives, and downloads further malware. The worm embeds code in a JPEG comment field of an ambiguously named file “image.jpg” or “imwin.jpg”. Previewing such files as images remains innocuous, as picture viewers tend not to execute meta data by default. This is unfortunately not the case when the file is run through the VB script engine, which is happy to interpret the same JPEG comment 0xFFFE header bytes to indicate Little-Endian UTF-16 encoded data and execute the remaining portion of the file as code. ...

April 3, 2010 Â· 1 min Â· 154 words Â· Omid Farhang

Running executables in PDF: it’s a feature

Didier Stevens, security professional and blogger, has found a “feature” in the PDF file format that makes it possible to package an executable in a PDF file which will run in Foxit PDF reader or run in Adobe Reader with a bit of social engineering. “With Adobe Reader, the only thing preventing execution is a warning. Disabling JavaScript will not prevent this (I don’t use JavaScript in my PoC PDF), and patching Adobe Reader isn’t possible (I’m not exploiting a vulnerability, just being creative with the PDF language specs).” ...

March 31, 2010 Â· 1 min Â· 210 words Â· Omid Farhang

EXEs in word docs

Today, our friends at Trend Micro blogged about a new attack vector using Microsoft Word documents. We saw this as well last week, and have written a detection for the dropped trojan. It’s not just a “lawsuit” that’s being spammed, we also picked up another form of this attack in our honeypots over the weekend: When you open the Word document, you see a “PDF”, but it’s actually not. It’s a JPG, which links to an executable. ...

March 30, 2010 Â· 1 min Â· 168 words Â· Omid Farhang

Back to Basics with Fake AV

We’ve been seeing Fake AV programs getting more convincing for a while now. Some of the tricks employed by the guys behind these rogue programs include Windows-7-style fake scanners, in-browser “scanners”, and program features that ape other aspects of the operating system. Yesterday, though, we came across a misleading application called AntiVirusDemoFraud that is—how to say?—possibly a little less sophisticated than some in terms of user interface design. ...

March 30, 2010 Â· 1 min Â· 130 words Â· Omid Farhang

Child Tax Credit is the New Phishing Bait

Who wouldn’t want some tax benefits in the current economic times? Don’t phishers and scammers know that all too well! In a new phishing scheme, We found that Child Tax Credit is being used as bait to lure parents to disclose their financial data. This attack specifically tries to convince users to make claims for credit and lower their tax burden by using their children’s education expenses. According to the Internal Revenue Service (IRS) website [PDF], taxpayers may be able to reduce their federal income tax by up to $1,000 for each qualifying child. Making use of this information, spam email discusses the expensive education of children and quickly advises recipients to use this expense to make claims for tax credits under the numerous tax benefits provided by the IRS. They make a further appeal that as a U.S. citizen or resident, recipients should apply for their tax returns. According to the email, users can get a tax refund of $75,000 for their children’s education. To apply for a refund, users need to complete a form attached to the email message. The fraudulent email has an HTML attachment named “#1924819299.pdf.htm”. ...

March 26, 2010 Â· 2 min Â· 364 words Â· Omid Farhang

The Facebook Dislike Button Likes Hotbar

Not so long ago, examples of fake Firefox websites / downloads were in the news with the sites involved serving Hotbar installs. It seems the tactic of offering up Firefox (but giving you something else entirely) is going to be around for a little while. Below is a site promoting a Firefox .xpi called “The Dislike Button”, designed to let you add an “I dislike this” note to Facebook posts: ...

March 23, 2010 Â· 2 min Â· 246 words Â· Omid Farhang

Using Windows “hosts” file to cut off the help line

We found this interesting and malicious little mechanism. The hosts file on a machine under investigation was modified to redirect the victim’s browser to a well known legitimate site (in this case google.com) whenever he attempted to contact a list of nearly 400 sites. The list was a “Who’s Who” of the anti-malware world – most places where someone with an infected machine would go to get help. The altered hosts file he found contained many lines beginning with ‘#’ followed by gibberish. These would be seen as comments by any browser and ignored. Concealed among the commented lines are lines containing the domain name redirections. When the commented lines are stripped, we find all the listed security related websites being redirected to “209.85.129.99” which is the IP address for google.com. ...

March 23, 2010 Â· 1 min Â· 194 words Â· Omid Farhang

Icelandic Volcano Erupts, Fake Antivirus Spews Forth

Yesterday there was a volcanic eruption in Iceland, near the Eyjafjallajoekull glacier, that has led the Icelandic authorities to declare a state of emergency in southern Iceland. People living nearby have been evacuated in case of glacial melt water flooding and the airspace near the now active volcano is effectively closed off. As you have probably already guessed, any event which commands a high level of public interest will be pounced on quickly by the makers of fake antivirus software in order to make a quick buck. This incident is no exception. ...

March 22, 2010 Â· 3 min Â· 554 words Â· Omid Farhang

Merogo SMS worm

We’re investigating a series of SMS Worms, found in the wild in China. Known as Trojan:SymbOS/MerogoSMS, these worms try to spread on Symbian Series 60 3rd Edition devices. Symbian continues to be by far the most common smartphone operating system in the world. These worms spread by sending text messages to other phones. These text messages contain variable messages (in Chinese), and a link to a website. If the link is followed, user is prompted to install an application – infecting the phone and restarting the SMS spreading. ...

March 22, 2010 Â· 1 min Â· 204 words Â· Omid Farhang

Google search reveals 3 million pages link to rogue AVs

Do you know what the latest version of Adobe’s Flash Player is? If you don’t, you may very well fall for this: Flash Player 11? There are more than 3 million pages linking to this alleged version 11: Most pages are from unsanitized forums, but there is even a Google Ad for it! Ooooops
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March 22, 2010 Â· 2 min Â· 228 words Â· Omid Farhang