Security Group Warns of hole in Linux kernel that could be used by malicious hackers to take control of systems using the popular open source operating system. America Online will give its customers built-in software to detect and remove “spyware,” hidden tools that can monitor Web surfers’ online habits for marketing purposes. White House press secretary declines to say whether Bush thinks aides should sign forms that would release reporters from any pledges of confidentiality regarding the leak of the identity of CIA operative Valerie Plame.”]