Aside from patching a major WebKit bug with iOS 14.5.1 and other updates for Apple devices, the same protection is now available on older iPhones incompatible with iOS 14.
iOS 12.5.3 launches on older iPhones
As detailed in a support document on Apple's website outlining the security content of the iOS 12.5.3 update, a total of four WebKit-related security flaws were patched in iOS 12.5.3. WebKit is a layout engine powering Apple's Safari browser and all iOS browsers.
Due to what Apple describes as "a buffer overflow issue," someone could put together maliciously crafted web content that, when processed by iOS, could lead to arbitrary code execution. If security and privacy are important to you, you definitely don't want your device to run code that some bad actor has managed to inject via web content.
Three instances of this vulnerability have been discovered in the WebKit engine while a fourth instance affects WebKit's storage system. iOS 12.5.3 fixes the flaw on these devices:
- iPhone 5s
- iPhone 6
- iPhone 6 Plus
- iPad Air
- iPad mini 2
- iPad mini 3
- iPod touch (sixth generation)
"Apple is aware of a report that this issue may have been actively exploited," says Apple. The memory corruption issue was addressed "with improved state management."
If some bad people out there have exploited this flaw to their advantage, and Apple has been aware of this, then you better update to stay on the safe side!
How to Install iOS 12.5.3
To update your compatible iPhone, iPad, or iPod touch to iOS 12.5.3, use Apple's Software Update mechanism---simply launch the Settings app and go to General > Software Update.
If you see a message there confirming that new software updates are available, choose to install them immediately over the air. Your iOS device must be plugged into power and connect to the internet with Wi-Fi before you can continue.
You may need to enter your device passcode to continue.
Do I Really Need to Update to iOS 12.5.3?
In a word, yes!
Everyone with an older iPhone laying around somewhere should install this update as soon as humanly possible. That's especially true if the device in question is being actively used by a friend or family member rather than just collecting dust in your drawer.
Updating to iOS 12.5.3 will ensure the device gets the latest protection from Apple against this particular WebKit vulnerability. Again, if Apple has publicly acknowledged that malicious users may have already actively exploited the flaw to their gains, then it means that both your privacy and security could be at risk if you don't have the update.
The latest and greatest versions of iOS, iPadOS, and other Apple operating systems don't work on all devices, but Apple is doing a tremendous job of keeping older hardware functional and safe to use with critical security updates like iOS 12.5.3.