Google’s corporate network was hackedbecause its workers were running rival Microsoft’s Internet Explorer browser, a point that didn’t escape the notice of security researchers and Web users.

“More interesting than the IE zero-day, is why wasn’t Google running Chrome?” asked Andrew Storms, director of security operations at nCircle Network Security, shortly after Microsoft issued a security advisory that told users of a critical, unpatched bug in Internet Explorer (IE).

Thursday, Microsoft acknowledged that the IE exploit had been used in the attacks against Google and other major corporations. “We have determined that Internet Explorer was one of the vectors used in targeted and sophisticated attacks against Google and possibly other corporate networks,” said Mike Reavey, director of Microsoft’s Security Response Center (MSRC).

In fact, the malware that Microsoft and others researchers have examined was designed to exploit IE6, the eight-year-old browser that’s most often used with Windows XP.

Others, in addition to Storms, questioned why Google wasn’t “eating its own dog food,” the phrase used to describe software development companies running their own products, often in early editions long before they’re made public. “I have to wonder, why the hell is Google using IE, and why IE6?” asked a Computerworld reader in a comment appended to a story on the IE bug. “In fact, why Windows-based servers? Eat your own dog food, Google.”

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