roundup The Conficker worm is keeping security experts on their toes, trying to scope out exactly how and when it might strike.
In a report on its battle against the persistent piece of malware, the Conficker Working Group says it was able to take down Conficker, but the worm itself still resides on millions of computers.
Among most prevalent June threats were a password-stealing Trojan, infected Windows media files, and a re-emerging Conficker, says Sunbelt Software.
Versions of the worm that went bust a year ago are still spreading and hiding on 6.5 million infected computers, security experts say.
Gumblar Web attack adds new domains, steals data, and continues to propagate after infections are cleaned up, making it worse than Conficker, ScanSafe says.
Looking beyond the Conficker worm, a new security report notes a 50 percent increase in the number of zombie PCs over 2008, plus cyberthreats such as Vundo.
Hundreds of PCs and medical devices at hospitals in the U.S. were found to be infected with the Conficker worm recently, a security expert says.
In addition to dropping a mystery payload on infected machines, the Conficker worm installs software that tries to dupe people into paying nearly $50 for fake antivirus software.
Security researchers at Trend Micro discover that the Conficker worm is updating itself but can't yet identify the payload
More than 700 computers at the University of Utah, including those at its three hospitals, have been infected with the worm.