JailbreakMe 3.0 was released earlier today which can be used to jailbreak iOS 4.3.3 on iOS devices including iPad 2. As we all know, Comex used a PDF exploit to jailbreak different iOS device but this exploit also makes the device vulnerable to hackers which might result in loss of important data. Think it this way, if someone install the same software on any other website and when you open that website, the hacker can have access to your device and can steal important data stored in your device.
To patch this loophole, Comex has also released a small tweak, PDF Patcher 2, which closes this loophole. So, it is strongly recommended that if you have jailbroken your device, you should install this patch right away to protect your device from unauthorized use.
To jailbreak your device, simply open Cydia, search PDF Patcher 2 and install the patch. This is a big flaw in iOS and hopefully, Apple will release an update to patch this loophole. But till they do, it is recommended that you install this tweak.