Apple said it will issue a patch that will close a PDF hole in iOS. Though this security hole is well known by iOS owners, it made headlines recently when the German government issued a malware warning about this "critical weakness" in Apple's iOS operating system. As it has done in the past with other security issues, Apple will release an update in the coming weeks to close this hole.
Those that jailbreak their iOS devices will want to avoid this update. The exploit that Apple will patch is the same one used by Comex in jailbreakme, an online jailbreak tool. Ironically, those that want to close this exploit now can do so using this jailbreak tool. Just jailbreak your iOS device and install a security patch from Cydia.