A tool called HeapLocker is designed to prevent heap-spray attacks. The tool is the invention of Didier Stevens, a Belgian security researcher. It takes away techniques used to exploit memory-corruption bugs in Web applications. HeapSpray attacks have become a common method for attackers to exploit bugs in various applications. It uses pre-allocating portions of the process heap to prevent exploit code from allocating it. It also detects the use of a NOP-slide to get to an attacker s shellcode.
Source: https://threatpost.com/heaplocker-tool-protects-against-heap-spray-attacks-121410/74773/