Apple has released iOS 18.1.1, iPadOS 18.1.1 and macOS Sequoia 15.1.1 with fixes for actively exploited vulnerabilities.
Install the updates to protect your device by navigating to General > Software Update in the Settings app on your iPhone or iPad, or the System Settings app on your Mac.
The updates address vulnerabilities in WebKit and JavaScriptCore, used by Safari and all iOS browsers, providing improved state management and checks.
Apple is aware that the vulnerabilities may have been actively exploited on Intel-based Mac systems, so it is important to update your iPhone and iPad as well.