Apple has disclosed serious security vulnerabilities for iPhones, iPads and Macs, which could potentially allow attackers to take complete control of devices.
Apple added that it is "aware of a report that this issue may have been actively exploited".
Security experts have advised users to urgently update affected devices - the iPhone 6S and later models, newer iPads, and Mac computers running macOS Monterey.
It also impacts some iPod models.
In a security update on its support page, Apple said one of the flaws means a malicious application "may be able to execute arbitrary code with kernel privileges" - which TechCrunch describes as meaning full access to the device.
TechCrunch reported that the other - a WebKit bug - could be exploited if a vulnerable device accessed or processed "maliciously crafted web content [that] may lead to arbitrary code execution".
The warning to users comes ahead of its traditional September launch of the latest iPhone - expected this year to be named the iPhone 14.