is an independent security researcher, who with Miller and Dai Zovi, launched a 2010 effort they dubbed that proposed researchers should be paid for their work because vulnerabilities have value.

ASLR, or "address space layout randomization," is an anti-exploit technology that randomly assigns data to memory to make it tougher for attackers to determine the location of critical operating system functions, and thus make it harder for them to craft reliable exploits.

Windows, for example, leans on ASLR, but Apple's current operating system -- 2009's Snow Leopard -- relies on partial ASLR that doesn't randomize important components of the OS. Microsoft has included ASLR in Windows since Vista's late 2007 debut.

After Snow Leopard's August 2009 launch, Miller said by not fully implementing ASLR.

Apple has not disclosed a ship date for Lion -- saying only that it will be available "this summer" -- or its price. Historically, the company has priced its operating system upgrades at $129 for a single license, $149 for a five-license package, although it departed from that practice with Snow Leopard when it priced Mac OS X 10.6 at $29 and $49, respectively.