A week ago, it was found out that about 600,000 Macs were found to be infected by a Flash Malware code-named ”Flashback Trojan Horse”, which would only trigger when one allows to install a rouge file which represents in the form of a Flash Player installer and if installed, disabled the Automatic Malware definition updates for the Mac.
When Apple found out a whiff of this, it was taken aback by the news and promised that it would soon release a fix for the removal of the Trojan. When Apple was busy developing the update, many tools arrived claiming to remove the malware, the best one among them was F-Secure. But now, Apple has kept its promise as usual and released a Java update and stated the following for it:
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.
So all Mac users with Java installed, make sure to install this update.
Source : Apple Support