Protect your machine on a
P2P network

File extensions - Part 2

Remember: This information refers to P2P network downloads only. All file types have their legitimate uses, so if you're looking around your hard drive and find files that have been labelled below as dangerous, leave them alone, they're probably supposed to be there.

The grey areas

Embedded active content

There are certain files that you will come across when file sharing on a P2P network which are regarded as ‘safe’, in that they won’t contain malware, but can be used to access it online after they're activated. The most notorious for this problem are the Windows Media files - WMA (Audio) and WMV (Video) which can include what's known as 'active content'.

Without getting too technical, active content can be used to acquire licences online for copyright protected material, or be employed as a promotional tool by opening a web page asking if you want to buy something.

That's the way it's supposed to work anyway. Unfortunately, this feature can also be used to acquire viruses, spyware, and other dangerous things.

Windows Media files are, of course, perfectly safe if you have created them yourself and many are shared without any trouble at all. The problem is that the fake files are difficult to spot, and can seem perfectly legitimate in their size and labelling.

The easiest solution is to simply ignore them when they show up in your search results. If you're a more proficient downloader, then you can always instruct your software to filter out any file extensions you don't want.

Non-executable files that can contain malicious content

Archives and compressed files

These are very common on every P2P network. An archive is a file that contains many other files, which need to be ‘unpacked’ before they can be used. Compressed files are pretty much the same thing, except that the end result is smaller than the original file, or group of files.

Archive and compressed file types

Archives and compressed file formats are perfectly safe, but their contents may harbour something unhealthy. To be absolutely sure, always scan an archived file with your anti-virus software.

Become an expert downloader with the step-by-step tutorials and more in
'The Essential Guide to Downloading'

P2P network - File extensions (Top)