“A short while ago, slipstream/RoL dropped an exploit for the ASUS memory mapping driver (ASMMAP/ASMMAP64) which was vulnerable to complete physical memory access (read/write) to unprivileged users, allowing for local privilege escalation and all sorts of other problems. An aside to this was that there were also IOCTLs available to perform direct I/O operations (in/out instructions) directly from unprivileged usermode, which had additional interesting impacts for messing with system firmware without triggering AV heuristics.
[…]
In addition to the ASMMAP bugs, I also reported the exact same bugs in their UEFI update driver (AsUpIO.sys). This driver is deployed as part of the usermode UEFI update toolset, and exposes almost identical functionality which (as slipstream/RoL pointed out) is likely from an NT3.1 example driver that was written long before Microsoft took steps to segregate malicious users from physical memory in any meaningful way.”
[…]
https://codeinsecurity.wordpress.com/2016/06/12/asus-uefi-update-driver-physical-memory-readwrite/
Firmware Security 