Update ASAP your iPhone / iPad to iOS 14.4 / iPadOS 14.4
As we can read on https://support.apple.com/en-us/HT212146
“Webkit: Impact: A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.
Kernel: Impact: A malicious application may be able to elevate privileges. Apple is aware of a report that this issue may have been actively exploited.”