Flaws in both pieces of software could introduce malicious MP3 or Windows Media files--which sound identical to unmodified music--into the file-swapping systems, said George Kurtz, CEO of Foundstone.
"These particular vulnerabilities are definitely attack vectors for any people or entity that is looking to go after those that are taking part in file-swapping activities," he said.
The music industry and Hollywood are eyeing such hacking tactics as a way to stop file swappers from trading copyrighted music in the future. A bill sponsored by Rep. Howard Berman, D-Calif., and Howard Coble, R-N.C., and introduced into the U.S. House of Representatives in July, would allow copyright owners limitedinto peer-to-peer networks.
Such attacks could take advantage of flaws similar to the two found by Mission Viejo, Calif.-based Foundstone.
The flaw in Windows XP can force the operating system to run code when a music file is played by Windows Explorer, the operating system's file-browsing application. Even placing the mouse pointer over a file icon--opening a preview of the file--could trigger the file's payload, if it has one. The vulnerability does not affect the Windows Media Player, according to details posted by Microsoft in its advisory.
The vulnerability occurs because certain attributes of the files can be loaded with bad data that affect the amount of memory that Microsoft's Windows allocates for the information. Known as a buffer overflow, such problems are a common software security problem.
People who use NullSoft's popular WinAmp software also have to watch out, said Foundstone's Kurtz. WinAmp has a similar flaw that allows code to run when certain multimedia tags in MP3 and WMA files are loaded with too much data. Kurtz said that the company has notified NullSoft and has a patch prepared. A representative for the software maker couldn't be reached for comment.
This is the second time in recent months that Microsoft has had a problem with a common multimedia format. In November, the company warned that its operating system's mishandling of the PNG (portable network graphics) image format could allow a malicious program to compromise a person's computer. Microsoft laterof that vulnerability to "critical."
News.com Special Report
20 minds on tech's future
Other multimedia formats are also becoming targets for Internet attacks. Web software maker Macromedia warned last week that a flaw in its Shockwave Flash Player, a popular browser plug-in for animating Web graphics, could leave Internet users open to attack.
The patch for Windows XP is available through Microsoft's Windows Update service. The newest version of NullSoft's WinAmp is available on the company's WinAmp site.