You can update your iPhone to iOS 16.6.1 by heading to the Settings app, choosing General, then choosing Software Update. The build number for today’s update is 20G81. It’s available for any iPhone capable of running iOS 16, which includes the iPhone 8 and newer.
Apple’s release notes for iOS 16.6.1 aren’t very detailed and simply say: “This update provides important security fixes and is recommended for all users.”
Apple will likely update its dedicated “Apple security releases” webpage with details on the vulnerabilities patched in today’s update soon. (Update: More details now available here.)
Here are the other updates from Apple today, all of which Apple says include “important security fixes.”
iPadOS 16.6.1, build number: 20G81 watchOS 9.6.2, build number: 20U90 macOS Ventura 13.5.2, build number: 22G91