Seculert researchers are reporting that the new Citadel Trojan, based on Zeus, is spreading rapidly thanks to an open source development model.

"'Seculert's Research Lab discovered the first indication of a Citadel botnet on December 17th, 2011,' the security company said Wednesday in a blog post," writes Computerworld's Lucian Constantin.

"The most interesting aspect of Citadel is its development process, which is similar to the ones behind community-supported open source projects," Constantin writes. "'Similar to legitimate software companies, the Citadel authors provide their customers with a User Manual, Release Notes and a License Agreement,' Seculert said."

Go to "Citadel banking malware is evolving and spreading rapidly, researchers warn" to read the details.

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