With compiler, runtime library and operating system support, Intel MPX claimed to enhance security to software by checking pointer references whose normal compile-time intentions are maliciously exploited at runtime due to buffer overflows.
In practice, there have been too many flaws discovered in the design for it to be useful, and support has been deprecated or removed from most compilers and operating systems.
Intel has listed MPX as removed in 2019 and onward hardware in section 2.5 of its Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 1.
[9] A study examined a detailed cross-layer dissection of the MPX system stack and comparison with three prominent software-based memory protection mechanisms (AddressSanitizer, SAFECode, and SoftBound) and presents the following conclusions.
According to their publication, the researchers were able to leak information through a Flush+Reload covert channel from an out-of-bound access on an array safeguarded by the MPX system.