A hacker has released attack code that could be used to exploit a critical bug in some versions of the Windows operating system. Microsoft patched the flaw, which affects older versions of Windows, on Oct. 9. When the Image Viewer tries to open a maliciously encoded TIFF file, it can be tricked into running unauthorized software on the PC.
A sample of the exploit was posted Monday to the Milw0rm Web site. The code has not yet been used in online attacks, according to Symantec, which issued an alert Monday. Symantec recommends that Windows users install the MS07-055 update as quickly as possible. Microsoft took the unusual step of issuing its own security update for Kodak"s software, because the image viewer (formerly known as the Wang Image Viewer) had shipped in Windows 2000 systems by default.