In May of 2008, researchers found a flaw in the Debian GNU/Linux operating system's random number generator, making any OpenSSL keys generated during the past 20 months so predictable that they could be correctly guessed in a matter of hours.
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Debian GNU/Linux, a particular distribution of the Linux operating system, is the result of a volunteer effort to create a free Unix-compatible operating system complete with a suite of applications. Like any operating system, it provides services to application programs that run on it. To provide cryptographic services such as Secure Sockets Layer (SSL), the OS uses the open source OpenSSL cryptography library.