No, Seriously, Just Disable Java in Your Browser Right Now

NOTE: I have already acted on this advice.

Will Oremus in Slate:

So while many media reports will direct you to the Oracle website to promptly install Java 7 update 11, there remains a far better option. Unless you’re one of the few Web users who regularly uses an important site that requires Java, take the advice of security experts like Adam Gowdiak of Security Explorations and H.D. Moore of Rapid7 and just disable it in your browser already.

As noted before, disabling the Java plug-in on your Web browser doesn’t require uninstalling it from your machine entirely, and it won’t prevent you from Java-based software outside of your Web browser. It just means that you’ll see an image like the screenshot above when you happen to visit one of the relatively few remaining websites that use Java applets. If you find you really need it for some sites, you can always disable it in your main browser but keep it enabled in a secondary browser that you use just for those sites.

Basic instructions for unplugging Java from your browser are below, and more comprehensive how-tos are available here and here. Note: Do not confuse Java with Javascript, which is unrelated and is essential to the proper functioning of far more websites. Disable Java, but leave Javascript enabled. If you have more questions, the blog Krebs on Security has an excellent FAQ here. (No, you aren’t necessarily safe just because you don’t visit sketchy websites, or because you’re using Linux or a Mac.)

More here.