PCWorld: Joe Stewart, director of malware analysis at SecureWorks, has tipped security researchers at the Shadowserver Foundation to a new attack from an old botnet. The Pushdo botnet (also known as Pandex or Cutwail) has been using infected computers to attack more than 300 major sites, including the FBI, Twitter, and PayPal.
In the past, the Pushdo botnet has been used to send out spam. However, it seems to have been recently updated so that it now tries to make SSL connections with targeted Web sites.
A spokesperson for the Shadowserver Foundations says, "We hope to put out an updated post that can help our system administrators associated with these Web sites soon."