I make that assumption because MIE quite evidently relies on both hardware (the processor), as well as software – and the new iPhones introduce new chips which, logically, will eventually in some form extend to Apple’s PCs and tablets.
How does MIE work?
In brief, the protection relies on both hardware and software with key components including secure typed memory allocators, Enhanced Memory Tagging Extension (EMTE) in synchronous mode, and Tag Confidentiality Enforcement. What are these?
- Secure typed memory allocators are Apple’s new system for memory management that secures memory handling at the hardware/software level.
- Enhanced Memory Tagging Extension is Apple’s strengthened version of ARM’s Memory Tagging Extension (MTE). It assigns tags to chunks of memory and to every pointer to that memory so that when an app accesses memory the processor can check all the tags line up. If they don’t, access is blocked.
- Tag Confidentiality Enforcement: This keeps those randomized tag values secret and ensures leaked data doesn’t include the values assigned to those tags.
These three technologies work together to block common memory attacks such as buffer overflows and use-after-free memory exploits, even at kernel level. This means that if malware tries to use a block of freed memory or tries a brute force attack or attempts to leak tag values, the tech prevents it. For a deeper dive into how the technology operates I urge you to look at Apple’s own guidance.
This story originally appeared on Computerworld
