Trailrunner7 writes with this excerpt from Threatpost: "Mozilla has made a change in Firefox that will block all of the older versions of Java that contain a critical vulnerability that's being actively exploited. The decision to add these vulnerable versions of Java to the browser's blocklist is designed to protect users who may not be aware of the flaw and attacks. 'This vulnerability — present in the older versions of the JDK and JRE — is actively being exploited, and is a potential risk to users. To mitigate this risk, we have added affected versions of the Java plugin for Windows (Version 6 Update 30 and below as well as Version 7 Update 2 and below) to Firefox's blocklist. A blocklist entry for the Java plugin on OS X may be added at a future date. Mozilla strongly encourages anyone who requires the JDK and JRE to update to the current version as soon as possible on all platforms,' Mozilla's Kev Needham said."