Never let it be said that Apple isn’t quick to address flaws in their systems, provided they are fixable. This afternoon, Apple launched iOS 4.0.2 for the iPhone and iOS 3.2.2 for the iPad. Both updates address the PDF-based stack buffer overflow hack warned about by Germany’s Office for Information Security and other consumer safety advocates last week, which would have allowed malicious hackers to gain control of users’ systems with surprising ease. Here’s the official wording from the update:

A stack buffer overflow exists in FreeType’s handling of CFF opcodes. Viewing a PDF document with maliciously crafted embedded fonts may allow arbitrary code execution. This issue is addressed through improved bounds checking.

Unfortunately, that is the same exploit used in the popular new browser-based jailbreaking website, JailBreakMe.com. Once patched with 3.2.2, iPad users will have that particular avenue shut down entirely. There remain ways to downgrade firmware for the use of this our previous methods of jailbreaking, but they lack the elegant simplicity of the JailBreakMe.com solution, which appealed to the less technologically-inclined as well.

If you have a jailbroken iPad and want to go back to normal: Download and install the update. It should eliminate your jailbreak and all unauthorized apps from Cydia and return it to a normal state.

If you have a jailbroken iPad and want to keep it that way: Do not under any circumstance install the update. It adds no features and its sole purpose is to close the security loophole. You’re not missing out on anything.

If you haven’t jailbroken your iPad yet, but want to: Go to JailBreakMe.com now before the automated update process runs its course. There’s still time!

If you haven’t jailbroken your iPad, and have no interest in it: Install the upgrade and relish the sweet feeling of security afforded by Apple’s patching process.