iPhone users should update to iOS 9.3.5 right now
The latest point release for iOS addresses serious security flaws, so if you’re running iOS 9, you should update today.
We’re most likely only a matter of weeks away from Apple releasing the iPhone 7 and with it, iOS 10, so it’s a little surprising to see Apple pushing out one last point release for iOS 9. Still, that’s what it has done, but not with a focus on new features or functionality. Where iOS 9.3.4 largely existing to lock down a route to jailbreaking, iOS 9.3.5 instead addresses some serious "zero day" exploits that could leave your data exposed to malicious parties.
Apple’s security advisory for iOS 9.3.5 states that it addresses exploits that could affect the operating kernel, memory corruption issues and the possibility for malicious web sites to execute arbitrary code on your iOS 9 device. While the company that originally identified the exploits noted that previously they would only have been used against specific high-value targets, with the publicity around them it’s more likely that criminal types would add them to their arsenal of exploits, so updating would be exceptionally wise.
How do I update my iOS device?
If you haven’t already been prompted to do so, head to Settings>General>Software Update. If you’re running an applicable device (which is pretty much any iOS 9-capable gadget) you should be prompted to download the update and apply it. As it encompasses the code found in iOS 9.3.4, that does mean that if you’re using a jailbroken iPhone or iPad, it will remove the jailbreak.
What does this mean for iOS 10?
It appears at this stage that the exploits in question don’t apply to iOS 10, so if you’re running the beta version of iOS 10 on your device, you should be secure, at least until malicious types work out the next exploit.