Microsoft Defends Win 7 Security After Pwn2Own
Last week we reported that during Pwn2Own, two hackers were able to sidestep Windows 7's data execution prevention (DEP) and address space layout randomization (ASLR), and hack into Internet Explorer 8 and Firefox 3.6. One of the hackers, Peter Vreugdenhil, a freelance vulnerability researcher from the Netherlands, said that he used "fuzzing" to uncover two vulnerabilities in a fully-patched version of 64-bit Windows 7.
"I started with a bypass for ALSR which gave me the base address for one of the modules loaded into IE. I used that knowledge to do the DEP (data execution prevention) bypass,” Vreugdenhil said last week.
Days later, Pete LePage, a product manager in Microsoft's Internet Explorer developer division, came up to bat for IE's Protected mode, DEP and ASLR in a recent blog, saying that defense-in-depth techniques aren't designed to prevent every attack forever. Instead, they're in place to make it that much more difficult to actually find and exploit a vulnerability.
