The developer builds a security-critical protection mechanism into the software, but the processor optimizes the execution of the program such that the mechanism is removed or modified.
A successful exploitation of this weakness will change the order of an application's execution and will likely be used to bypass specific protection mechanisms. This bypass can be exploited further to potentially read data that should otherwise be unaccessible.
In theory this weakness can be detected through the use of white box testing techniques where specifically crafted test cases are used in conjunction with debuggers to verify the order of statements being executed.
CVE-2017-5715Intel, ARM, and AMD processor optimizations related to speculative execution and branch prediction cause access control checks to be bypassed when placing data into the cache. Often known as "Spectre".
CVE-2017-5753Intel, ARM, and AMD processor optimizations related to speculative execution and branch prediction cause access control checks to be bypassed when placing data into the cache. Often known as "Spectre".
CVE-2017-5754Intel processor optimizations related to speculative execution cause access control checks to be bypassed when placing data into the cache. Often known as "Meltdown".