Apple has announced a significant enhancement in memory safety for its iPhone 17 lineup, termed Memory Integrity Enforcement (MIE). This upgrade aims to address vulnerabilities exploited by spyware like Pegasus, enhancing security across the operating system and Apple’s hardware. MIE is characterized as a comprehensive, always-on protection that covers critical attack surfaces, including the kernel and numerous userland processes. This initiative is built on the Enhanced Memory Tagging Extension (EMTE), coupled with secure typed allocators and tag confidentiality protections.
The approach mirrors measures previously introduced by Microsoft for Windows 11, focusing on memory integrity security features to mitigate risks associated with speculative-execution vulnerabilities. Additionally, Apple references efforts by ARM concerning the Memory Tagging Extension (MTE), which has also been adopted by Google’s Pixel devices starting with the Pixel 8 series.
Apple claims its implementation stands out by providing default protection for all users and enhancing the security features of its A19 and A19 Pro chips. Furthermore, improvements have been made for older hardware that lacks support for the new memory tagging capabilities. Notably, the company states that its mitigation for Spectre V1 leaks incurs virtually no CPU cost, addressing concerns related to performance impacts from memory integrity and other security measures.
The GrapheneOS project, known for its security-focused initiatives, acknowledged the security enhancements but raised concerns about how Apple’s presentation compared iOS security to features like MTE, which are already available for Android. As the iPhone 17 and iPhone Air updates are rolled out, the effectiveness of these new security measures will be evaluated, especially as potential attackers seek to breach their defenses.
Source: https://www.theverge.com/news/775234/iphone-17-air-a19-memory-integrity-enforcement-mte-security