Trailrunner7 writes with this from ThreatPost: "Researchers have made a huge dent in the Pushdo botnet, virtually crippling the network, by working with hosting providers to take down about two thirds of the command-and-control servers involved in the botnet. Pushdo for years has been one of the major producers of spam and other malicious activity, and researchers have been monitoring the botnet and looking for ways to do some damage to it since at least 2007. Now, researchers at Last Line of Defense, a security intelligence firm, have made some serious progress in crushing the botnet's spam operations. After doing an analysis of Pushdo's command-and-control infrastructure, the researchers identified about 30 servers that were serving as C&C machines for the botnet. Working with the hosting providers who maintained the servers in question, the LLOD researchers were able to get 20 of the C&C servers taken offline, the company said."