Not long to go until iOS 5 finally makes it to your smartphone or tablet. But in the meantime, Apple still needs to take care of everyday business, with iOS 4.3.4 now available to keep everything secure from outside threats.The update closes a hole in the security of both the iPhone and iPad, specifically, it 'fixes security vulnerability associated with viewing malicious PDF files'. That hole was flagged up earlier this month and has been used by JailbreakMe.com to allow users to 'jailbreak' their Apple device. You could argue that doing so isn't a major issue.However, that same hole also makes your device vulnerable to hackers, who can use it to access and acquire your personal details. Basically, if it can use the hole to access for one task, it can be used to access for something far, far worse. In fact, just clicking on an infected PDF file would be enough to infect your device without you knowing.Reason enough to go download the update now. Just hook up to iTunes to get it.