Apple has released the iOS 4.3.4 update for iPhone, iPad and iPod touch devices. This update should be available to you now just by plugging your device into iTunes and mashing the check for updates button.
This patch fixes the PDF vulnerability that allows for JailbreakMe.com to jailbreak these devices. This means that if you’re the owner of a jailbroken device and wish to keep it that way, you should not update.
Impact: Viewing a maliciously crafted PDF file may lead to an unexpected application termination or arbitrary code execution
Description: A buffer overflow exists in FreeType’s handling of TrueType fonts. Viewing a maliciously crafted PDF file may lead to an unexpected application termination or arbitrary code execution.
Since this vulnerability fixes a potentially harmful security hole in iOS 4.3.3, all other users of iDevices should upgrade now.
The Verizon iPhone uses a different version of the iOS software than GSM phones. That versioning has led to a fork in the firmware. For users of Verizon iPhones, Apple has released iOS 4.2.9, which provides the same fixes as iOS 4.3.4.