For his exploit expertise, Vreugdenhil, a Dutch freelance researcher, last month won $10,000 during the Pwn2Own hacking contest. His one-two punch was called "particularly impressive" by the contest organizer because it sidestepped DEP and ASLR, two cornerstones of Vista's and Windows 7's security.
Microsoft has patched untouchable vulnerabilities before, Bryant confirmed, citing several examples, including MS09-032 , a July 2009 update that disabled a company-made ActiveX control said to be unexploitable in Vista or Server 2008. Prior to that, Microsoft issued MS09-015 (April 2009) and MS08-062 (October 2008) for similar defense-in-depth reasons.
"These are typically situations where the vulnerable code exists but is not accessed in any way by the system," said Bryant. "We feel it's important to continuously look at ways to reduce the overall attack surface, so defense-in-depth updates will continue to be offered to customers."
Storms argued that it was just Microsoft following established protocol. "This probably has more to do with the mechanics of Microsoft's SDL [software development lifecycle] than anything else," Storms said. "A bug was found and validated, they are thus committed to issuing the fix. All supported platforms must receive the fix, even if it means that the possibility of an attacker even thinking about exploiting it is unlikely."
Bulletin 7 has a back story that makes it more interesting than most. Microsoft doesn't map pre-patch bulletins to issues it has said will be addressed, but clues point to Bulletin 7 fixing a flaw in VBScript. Last month, a Microsoft advisory warned Windows XP users of a bug in the scripting language, and told them not to press the F1 key when prompted by a Web site.
Storms acknowledged that the situation was probably confusing to users, what with Microsoft claiming that Vista, Windows 7 and Server 2008 were not affected by the vulnerability, but still urging users to patch. But look at the bigger picture, he said.
"[Microsoft's] basically saying that in order for an attack to work, many layers would have to be peeled apart first, essentially making an attack unlikely," he said. "Yet, Microsoft is saying they are still bound by an obligation to issue the fix."
Microsoft will release the 11 security updates, including Bulletin 7, at approximately 1 p.m. ET today.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld . Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed . His email address is email@example.com .
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