Computer Programming Software Terms, Glossary and Dictionary
ASLR: Address Space Layout Randomization
Address Space Layout Randomization (ASLR) is a process which entails arranging the positions of major data areas randomly in virtual address space. This can include the base of the executable, libraries, heap, and stack. The chances of an attacker guessing where any of these randomly placed areas is 1 / 2b, where b is the number of bits of entropy used to determine the position of the data area. In many systems, 2b can be in the thousands or millions; on modern 64-bit systems, these numbers typically reach the millions at least.