Use of DNS Tunneling for C&C CommunicationsOften, virus writers don't even bother to run encryption or mask their communications. However, you do get the occasional off-the-wall approaches that don't fall into either of the categories. Take, for instance, the case of a Trojan that Kaspersky Lab researchers discovered in mid-March and which establishes a DNS tunnel for communication with the C&C server.
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Use of DNS Tunneling for C&C Communications
