nullmap

A very simple driver manual mapper based on my older voidmap and CVE-2023-21768 POC by chompie and b33f. Because the underlying IoRing post-exploitation memory r/w primitive is not handling many consequent reads and writes very well, I've decided to overwrite CR4 to disable SMEP/SMAP to execute the driver mapped in usermode. Tested on Windows 11 22H2 (22621.525).

Usage:

nullmap.exe <path_to_driver>

Possible problems:

• Manual mapped driver will be in a pool allocated by ExAllocatePool. If you want to use this for anything more serious you should consider finding a better way of memory allocation so it can't be dumped so easily.
• There is no easy way to read the original cr4 value which means that I had to hardcode the value that was there on my system. While it should be the same for most modern CPUs, you should still double-check that the value is correct.
• I've hard-coded offset to NtGdiGetEmbUFI since there is no easy way to sigscan it, which means that you will have to update this offset for your specific Windows build.
• It was written in one afternoon, it might not be the cleanest code base.

Video: