When you think of PDF (Portable Document Format) files, the program most commonly associated with them is Adobe Acrobat Reader. Part of the widespread popularity of this file format is that PDF files will look the same on all operating systems, such as Windows or Mac. This also makes it a prime candidate for the latest malware threat.
According to a recent article on TrustedSource.org, a new exploit toolkit is being used to target PDF files. It’s being called the ‘PDF Xploit Pack’ and could potentially be very dangerous. In case you didn’t know, an exploit is simply a program that takes advantage
of, or exploits, a flaw in another program. It’s the software equivalent of sneaking into a house through an unlocked window.
When your computer is infected with an exploit toolkit, the results vary wildly depending on the exploit. It is quite common that they will open up your PC to install other exploits or even turn your machine into a ‘zombie’ that sends spam. When your computer is infected, they can be quite difficult to clean, and formatting the hard drive to reinstall all your software is often the only solution.
What’s scary about this new exploit is that the PDF file format is so popular and widely distributed. This exploit basically embeds itself into an infected PDF, and when you open that file, the exploit is opened, too. In the past, similar methods have been used in executable (.exe) files. As a general rule, you should not open any executable files sent as email attachments. They are too susceptible to viruses.
Malware such as this new PDF Xploit Pack are often spread via email, though I haven’t personally seen it yet. That doesn’t mean it won’t start soon. What happens is you’ll get an email from an unknown sender and the message might seem a little off. Attached to the message will be a PDF file, and the intention is for you to open it. These type emails often take advantage of your curiosity, such as the widespread ‘greeting card virus’ problem of a few months back.
The best defense against these type exploits is to not open file attachments from unknown senders. However, some of these messages get into your address book and make it look they were sent from a friend. These can be particularly hard to spot for those people who don’t know any better. Be on the lookout for strangely worded, especially vague, messages that encourage you to open the attached file. If you aren’t certain
about the file, just don’t open it.
As always, make sure you keep your antivirus software and malware scanners running and updated. One anti-malware program that I recommend is Windows Defender, and it’s free from Microsoft. I’ve personally used it to clean problematic programs off several computers. You can download it here.