Not even two weeks have gone by since Comex released JailbreakMe 3.0 to jailbreak and iOS device running 4.3.3 and already Apple is releasing a fix. This is not really a surprise and it is actually more surprising that they did not have a fix sooner considering this update also fixes a very serious security hole. The same hole in security that Cydia is installed can also be used to farm your contacts database, accessing saved passwords, or activating your iPad or iPhone’s built-in camera. This was a big enough issue that even German officials stepped in and strongly suggested that Apple take care of this immediately, while warning consumers to avoid opening untrusted PDF files.
It should be noted that JailbreakMe 3.0 also fixes this hole after it is installed, and this could be useful to take advantage of before the official patch is released. It seems Apple devices are not as locked down as many seem to think, and when you consider that the iPhone 4 tracks your location to some degree, knowing that it can be downloaded via an exploit is not a pleasant thought.
I would like to mirror the Germans in saying that you should be aware of where you are downloading PDFs from until you have the patch applied.