Apple has just released an update to Java for OS X that effectively removes any traces of the notorious Flashback trojan from an infected system. The update can be downloaded now in Software Update on all Macs running Snow Leopard through Mountain Lion.
This Java security update removes the most common variants of the Flashback malware.
This update also configures the Java web plug-in to disable the automatic execution of Java applets. Users may re-enable automatic execution of Java applets using the Java Preferences application. If the Java web plug-in detects that no applets have been run for an extended period of time it will again disable Java applets.
This update is recommended for all Mac users with Java installed.
The update weighs in at about 70MB and should make your machine immune to any potential threat from Flashback. Previously, the only way to completely ensure safety from the Flashback malware was to disable Java in your browser.
Apple said a couple days ago that it was working on a tool to detect and remove Flashback, and it looks like said tool has been bundled into this Java update.