Local physical-memory writes via hard-coded MAC key

Hard-coded credentials in DirectIo64.sys in PassMark PerformanceTest, BurnInTest, and OSForensics allow local users to write physical memory. The driver accepts MD5 tags derived from an embedded eight-byte key, while its bit-clear IOCTL can alter the write-path gate so later requests skip MAC, size, and Vendor ID checks. A low-privileged process must obtain a driver handle; affected releases are PerformanceTest before 11.1 build 1012, BurnInTest before 11.1 build 1000, and OSForensics before 11.1 build 1016, and successful writes can alter kernel memory and support elevation to SYSTEM.