Along with new features, the iOS 18.3, iPadOS 18.3, and macOS Sequoia 15.3 updates that Apple released today include multiple security fixes, including a fix for vulnerability that may have been actively exploited on some devices.
According to Apple's security support document, there was a CoreMedia bug that could be used to elevate privileges. Apple says that it is aware of a report that the bug could have been actively exploited against versions of iOS before iOS 17.2. Apple fixed the issue with improved memory management.
Apple also addressed over 20 other vulnerabilities. One could allow an attacker with physical access to an unlocked device to access the Photos app even when an iPhone is locked, and there were several issues with AirPlay that could allow attackers to execute code or crash apps.
Two kernel vulnerabilities could let malicious apps gain kernel privileges, and there were a handful of WebKit fixes for Safari.
Because of the number of security issues fixed in the update, it is a good idea to update to the new software right away.
watchOS 11.3 and tvOS 18.3 also have a number of security fixes, so those updates should be installed as well. If you have macOS Sonoma or Ventura, Apple has released macOS 14.7.3 and macOS Ventura 13.7.3 with security improvements.
