Hackers extracted lists of files from computers that they contaminated with the virus that triggered cyberattacks last week in the United States and South Korea, police in Seoul said Tuesday. The attacks, in which floods of computers tried to connect to a single Web site at the same time to overwhelm the server, caused outages on prominent government-run sites in both countries. The finding means that hackers not only used affected computers for Web attacks, but also attempted to steal information from them. That adds to concern that contaminated computers were ordered to damage their own hard disks or files...