A few days ago, it was discovered that Java 7, (version 1.7) had been compromised. If you visit an infected website, your computer can be taken over silently. Java 6 does not have this vulnerability. Most Mac users do not have to worry about the Java exploit, because most Mac users are not running the exploited version of Java. The only way you can get this version on a Mac is to download it from the Oracle website manually. Java is not installed by default on a Mac, starting with OS X 10.7, Lion.
What about Windows users? You should be vigilant. Make sure you have strong internet security software in place. Google’s Chrome browser is apparently unaffected.
The good news? Oracle posted an update to Java on it’s website a few hours ago that fix the exploit. You can go to www.java.com, and then click on the Do I have Java link to see what version you have. You can also click on the Free Java Download button to download the latest version that has the fix. If you do not have Java running on your computer, no need to download it at all. If you do have Java, make sure you upgrade to the latest version.