Apple has released iOS 15.6.1, bringing security fixes which address kernel and WebKit vulnerabilities that could lead to arbitrary code execution.
Kernel
An application may be able to execute arbitrary code with kernel privileges. Apple is aware of a report that this issue may have been actively exploited.
Description: An out-of-bounds write issue was addressed with improved bounds checking.
Issues in the kernel are as bad as it can get and why this update to fix it is crucial.
WebKit
Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.
An out-of-bounds write issue was addressed with improved bounds checking.
Due to the severity of these critical security issues, it is highly recommended that users update to iOS 15.6.1 as soon as possible!
iOS 15.6.1 Availability
iOS 15.6.1 is available for iPhone 6s and later, iPad Pro (all models), iPad Air 2 and later, iPad 5th generation and later, iPad mini 4 and later, and iPod touch (7th generation)
You can download the update by opening the Settings app and going to General > Software Update.
