"Within the Microsoft organisation, access to Windows source code is said to be highly compartmentalized, making it easy for modifications to be inserted without the knowledge of even the respective product managers.
Researchers are divided about whether the NSA key could be intended to let US government users of Windows run classified cryptosystems on their machines or whether it is intended to open up anyone's and everyone's Windows computer to intelligence gathering techniques deployed by NSA's burgeoning corps of "information warriors".
According to Fernandez of Cryptonym, the result of having the secret key inside your Windows operating system "is that it is tremendously easier for the NSA to load unauthorized security services on all copies of Microsoft Windows, and once these security services are loaded, they can effectively compromise your entire operating system". The NSA key is contained inside all versions of Windows from Windows 95 OSR2 onwards.
"For non-American IT managers relying on Windows NT to operate highly secure data centres, this find is worrying", he added. "The US government is currently making it as difficult as possible for "strong" crypto to be used outside of the US. That they have also installed a cryptographic back-door in the world's most abundant operating system should send a strong message to foreign IT managers".
"How is an IT manager to feel when they learn that in every copy of Windows sold, Microsoft has a 'back door' for NSA - making it orders of magnitude easier for the US government to access your computer?" he asked."
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