The author of mass-mailing worm Bagle began distributing its source code and two new variants on Sunday, which could trigger another summer of misery for Windows users.
Infected PCs download a Trojan that effectively enlists that computer into the worm author's army of zombie PCs, which can be used to distribute spam and other malware and to launch distributed denial-of-service attacks. This weekend saw not only two new versions of the Bagle worm released, but also what appears to be the worm's original source code.
Mikko Hypponen, director of antivirus research at F-Secure, said he believes the source code is genuine. He added that it is written in pure assembly language, also known as assembler, which indicates the author responsible is a serious programmer and not a script kiddie. "Most e-mail worms are written in C, or partly in C and partly in assembler. There are not that many people that are this good in assembler any more, so it is a serious programmer behind it," said Hypponen.
News source: C|Net News.com