Torpig, also known as Anserin or Sinowal is a type of botnet spread through systems compromised by the Mebroot rootkit by a variety of trojan horses for the purpose of collecting sensitive personal and corporate data such as bank account and credit card information. It targets computers that use Microsoft Windows, recruiting a network of zombies for the botnet. Torpig circumvents antivirus software through the use of rootkit technology and scans the infected system for credentials, accounts and passwords as well as potentially allowing attackers full access to the computer. It is also purportedly capable of modifying data on the computer, and can perform man-in-the-browser attacks.
By November 2008, it was estimated that Torpig had stolen the details of about 500,000 online bank accounts and credit and debit cards and was described as "one of the most advanced pieces of crimeware ever created".[1]