Apple’s recent release of iOS 18.3 underscores the critical importance of timely software updates for iPhone users. This update addresses a significant number of vulnerabilities, a total of 29, including one that has been actively exploited by attackers. While Apple refrains from providing exhaustive details about the vulnerabilities to prevent malicious actors from capitalizing on the information before widespread adoption of the update, the urgency of the update speaks volumes about the potential risks. One confirmed exploited vulnerability resides within CoreMedia, identified as CVE-2025-24085. This flaw allows malicious applications to escalate privileges, potentially granting them unauthorized access and control. Apple has confirmed reports of this vulnerability being exploited on iOS versions prior to 17.2, highlighting the need for immediate action.
The scope of iOS 18.3’s security enhancements extends beyond the actively exploited vulnerability. Two critical bugs within the iOS Kernel, the core of the operating system, have been addressed. CVE-2025-24107, one of the Kernel flaws, allows malicious apps to gain root privileges, effectively granting them complete control over the device. The other Kernel vulnerability enables malicious code execution with Kernel privileges, posing equally serious risks. Furthermore, iOS 18.3 patches several vulnerabilities in WebKit, the engine powering the Safari browser. One such flaw in the WebKit Web Inspector opens the door to command injection, a technique where attackers trick an application into executing arbitrary commands on the operating system. The update also addresses vulnerabilities in AirPlay and Passkeys, preventing remote attacks that could lead to application termination, code execution, or unauthorized Bluetooth access.
The importance of updating to iOS 18.3 is emphasized by security experts. Sean Wright, head of application security at Featurespace, notes the “several important security-related fixes,” and strongly recommends immediate updating. He highlights the Kernel flaws as particularly concerning, potentially granting attackers full device control. The possibility of chaining these Kernel vulnerabilities with others, especially CVE-2025-24150, to facilitate remote exploitation further amplifies the risk. While many of the other addressed vulnerabilities are related to denial of service or privacy infringements, such as user fingerprinting, they still warrant attention. Significantly, Wright points out that the CoreMedia flaw could be exploited in iOS versions predating iOS 18, stressing the need for immediate migration to the latest version as older versions lack these critical security patches.
Michael Covington, VP of strategy at Jamf, emphasizes the breadth of the iOS 18.3 update, covering “a wide number of critical services,” including Accessibility, AirPlay, CoreMedia, Kernel, Passkeys, Safari, and WebKit. He notes that the release notes provide valuable insights into potential threat vectors. The patches address vulnerabilities related to bypassing locked apps, preventing memory corruption from local network attacks, blocking denial-of-service attacks, and enhancing web browsing security. Covington strongly advises both individual users and organizations to prioritize the installation of security updates, specifically citing iOS 18.3 as a crucial update for maintaining device security and protection against attackers.
Beyond security fixes, iOS 18.3 introduces changes to Apple Intelligence. For iPhone 15 and later models, AI features are automatically enabled. Users are advised to check their settings and disable these features if desired, considering the data requirements inherent in AI operation. While Apple’s AI features prioritize privacy, processing data on-device whenever possible and using secure Private Cloud Compute for more intensive tasks, the update introduces further integration with OpenAI’s ChatGPT for Siri. While Apple will request permission before sending data to ChatGPT, users should be aware that OpenAI’s privacy policies differ from Apple’s when utilizing this feature.
The release of iOS 18.3, alongside updates for other Apple devices, addresses a range of critical security flaws, including one actively exploited in the wild. The update is available for a broad range of devices, from iPhone XS onwards and various iPad models. Given the potential for serious security breaches, updating to iOS 18.3 is highly recommended for all eligible users. The update process is straightforward, accessible via Settings > Software Update on the iPhone. Prioritizing this update ensures the continued security and privacy of user data and device functionality. Delaying updates exposes users to unnecessary risks, emphasizing the urgency and importance of promptly installing iOS 18.3.
