A problem in Windows XP lets code be executed inside JPEG images

Microsoft published on Tuesday a patch for a major security flaw in its software's handling of the JPEG graphics format and urged customers to use a new tool to locate the many applications that are vulnerable. The problem is that it is possible to exploit a flaw in Windows that lets a hacker run a malicious program that is hidden inside a JPEG image. Windows users could fall prey to an attack just by visiting a Web site that has affected images.

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