Recently, instant messaging worms have become quite popular as a way to distribute malicious files. Since better anti-virus systems and years of everyone saying never to click on an unexpected email attachment have resulted in fewer issues with emailed malware, it didn't take long for malware writers to gravitate to the instant gratification of instant messaging -- sometimes using some basic chatbot skills to trick people. However, for the most part, the lack of interoperability between the various IM platforms has kept such viruses limited. Unfortunately, it looks like the latest outbreak works on the big three IM platforms at the same time. AIM, Yahoo and MSN are all impacted. In the meantime, consider it a holiday reminder that your friend/colleague/relative probably isn't sending you a link to a Santa Claus image.