I (re)Write the Songs: Taking Over Your Computer Via MP3 Files

Most folks who work with computers have a passing knowledge of hackers.  They're people who try to gain access to a computer that isn't theirs.  Access can be gained directly, by trying to access the computer either locally or remotely, or indirectly, by getting a user to run a program that has rogue code in it to give the hacker the access he wants.

People have wised up to some of the basic rules to avoid this kind of problem.  Don't run programs on your computer if you don't know where they've come from.  Install virus-scanning software on your computer, especially if you access the Internet.  Be very careful about copying data from publicly-accessed computer sites.  However, for every hole a user plugs, hackers can take advantage of other methods to create new ones.  One of the latest ways to gain control over a computer is through one of the most popular types of files being downloaded today: MP3 files.

MP3 is one of many formats that can be used to digitally store an audio recording on a computer or other electronic device for playback.  A formula is used to remove the parts of the recording that is either too high or too low for human hearing.  In addition, the data is compressed to reduce file size.  Finally, information about the recording is added to a header record before the file is saved.

So how does a hacker take advantage of the MP3 file format to gain access to your computer?  By taking advantage of the header record that's part of every MP3 file.  That record can contain anything, from the name of the recording, the artist who performed it, even the cover art from the album.  Proficient hackers can insert code into the header record that will give them access to the computer on which the MP3 file resides.  When the file is run (through a software program that plays MP3 files, like Windows Media Player or MusicMatch Jukebox), the header record is read.  Any executable code in the header will be run at that time.  And before you know it...BOOM!  You've just handed over control of your computer to somebody you don't even know.

How do you protect yourself against this kind of attack?  Even if virus scanning programs check the MP3 file header, the code found wouldn't necessarily register as a virus, especially if the code is home-grown.  Music services like iTunes, URGE, and the like use file formats other than MP3.  The services who do use MP3 check their files to make sure there's nothing unusual or suspicious about the file contents.  The possibility of getting a hacked MP3 file from these companies is exceedingly small.

So the best advice for preventing illegal access to your computer sounds like something you'd tell a toddler:  Don't take MP3 files from strangers.  If you don't know where the file came from, the more likely it is you'll end up with more than you bargained for.

Comment by Danny Davids^(13,043) (213 days 4 hours ago.)