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Next, Conficker A enters an infinite loop, within which it generates a list of 250 domain names (rendezvous points). The name-generation function is based on a randomizing function that it seeds with the current UTC system date. The same list of 250 names is generated every 3 hours, i.e., 8 times per day. All Conficker clients, with system clocks that are at minimum synchronized to the current UTC date, will compute and attempt to contact the same set of domains. When contacting a domain for which a valid IP address has been registered, Conficker clients send a URL request to TCP port 80 of the target IP, and if a Windows binary is returned, it will be validated via a locally stored public key, stored on the victim host, and executed. If the computer is not connected to the Internet, then the malicious code will check for connectivity every 60 seconds. When the computer is connected, Conficker A will execute the domain name generation subroutine, contacting every registered domain in the current 250-name set to inquire if an executable is available for download.