Methods and apparatus to protect memory from buffer overflow and/or underflow

A disclosed example to protect memory from buffer overflow or underflow includes defining an implicit bound pointer based on an implicit bound pointer definition in a configuration file for a memory region; instrumenting object code with an implicit buffer bound check based on the implicit bound pointer; and generating hardened executable object code based on the object code, the implicit buffer bound check, and the implicit bound pointer, the implicit bound pointer located in the hardened executable object code during a compilation phase to facilitate loading the implicit bound pointer in a global bounds table during runtime for access by the implicit buffer bound check.