Several open-source security systems --OpenBSD, PaX and Exec Shield -- already implement ASLR, which is described as a security feature that randomly arranges the positions of key data areas to prevent malicious hackers from predicting target addresses. ...
"[It] is a useful defense because it makes Windows systems look "different" to malware, making automated attacks harder," Howard said.
"In short, when you boot a Windows Vista Beta 2 computer, we load system code into different locations in memory. This helps defeat a well-understood attack called 'return-to-libc', where exploit code attempts to call a system function," Howard explained.
