About Rapid Security Responses for iOS, iPadOS and macOS

Rapid Security Responses deliver important security improvements between software updates.

Rapid Security Responses are a new type of software release for iPhone, iPad and Mac. They deliver important security improvements between software updates – for example, improvements to the Safari web browser, the WebKit framework stack or other critical system libraries. They may also be used to mitigate some security issues more quickly, such as issues that may have been exploited or reported to exist.

New Rapid Security Responses will only be delivered for the latest versions of iOS, iPadOS and macOS, starting with iOS 16.4.1, iPadOS 16.4.1 and macOS 13.3.1.

By default, your device will apply Rapid Security Responses automatically. If necessary, you’ll be prompted to restart your device. To check your device settings:

• iPhone or iPad: go to Settings > General > Software Update > Automatic Updates, then make sure “Security Responses & System Files” is turned on.

• Mac: choose Apple menu  > System Settings. Click General in the sidebar, then click Software Update on the right. Click the Show Detail button next to Automatic Updates, then make sure “Install Security Responses and system files” is turned on.

When a Rapid Security Response has been applied, a letter will appear after the software version number, for example: macOS 13.3.1 (a).

If you choose to turn off this setting or not to apply Rapid Security Responses when they’re available, your device will receive relevant fixes or mitigations when they’re included in a subsequent software update.

More details about a specific Rapid Security Response are available in the Apple security releases article.