After opening the file it will send a message to all online contacts of the affected user, stating "this picture never gets old". Each message has a link to a URL where users download a file that appears to be a JPEG image.
It also starts downloading spyware and popups and logs the Internet sites the infected users visit.
Trend Micro also warns: "This worm has backdoor capabilities. It opens a random TCP port and connects to the Internet Relay Chat (IRC) server xyz.legi0n.net. Once connected, it joins the IRC channel #fate, where it listens for commands from a remote malicious user. It then executes these commands locally on affected machines."More info at MacWorld