Arm published the Memory Tagging Extension (MTE) specification in 2019 as a tool for hardware to help find memory corruption bugs. MTE is a memory tagging and tag-checking system, where every memory allocation is tagged with a secret. The hardware guarantees that later requests to access memory are granted only if the request contains the correct secret. If the secrets don’t match, the app crashes, and the event is logged. This allows developers to identify memory corruption bugs immediately as they occur.
Did the article get edited? There is not much description of the field trip.
unfortunately a little light on the details. I'm very curious how the bug survived through MTE
Upon further reading on data only attacks
(https://www.usenix.org/publications/loginonline/data-only-at...)
This makes more sense. You don't trigger MTE since you're not doing anything for force MTE to take action the program isn't actually changing.
My other question would be, why didn't apple use fbounds checking here? They've been doing it aggressively everywhere else.
MTE plus fbounds checking everywhere should lead to an extremly hardened OS
Quite strange indeed, given that was one of the main points on their security conference a few months ago.
GPU memory/shaders/etc. isn't protected by MTE or PAC. They said "data-only", so I guess GPU commands could fit into this description.
Memory Tagging Extension
Arm published the Memory Tagging Extension (MTE) specification in 2019 as a tool for hardware to help find memory corruption bugs. MTE is a memory tagging and tag-checking system, where every memory allocation is tagged with a secret. The hardware guarantees that later requests to access memory are granted only if the request contains the correct secret. If the secrets don’t match, the app crashes, and the event is logged. This allows developers to identify memory corruption bugs immediately as they occur.
https://support.apple.com/guide/security/operating-system-in...
First Mozilla, now even Apple is making up fake vulnerabilities to hype up Mythos. /s