A new piece of Mac malware discovered Monday might be affecting around 4,200 Macs in the United States, researchers report. Fortunately, there's an easy way to tell if you've been infected.
Go to the Finder, click the "Go" menu, then click "Go to Folder…". In the window that pops up, copy this path and paste it into the text area: /Library/Application Support/JavaW — then click the Go button. If you just get a beep and a message that the window can't be found, you should be okay.