A vulnerability has been discovered in Microsoft's Picture and Fax Viewer that allows arbitrary code embedded in image files to be executed without user intervention. This vulnerability can be exploited by simply loading a picture from a malicious website or e-mail message. Microsoft is aware of the problem and is working on a fix. Until an update has been released, users are encouraged to exercise extreme caution when browsing the web or opening e-mails with embedded pictures. It is also important that Anti-virus and Anti-spyware applications be kept up-to-date.