U.S. authorities are investigating the theft of an estimated tens of millions of dollars from Citibank by hackers partly using Russian software tailored for the attack, according to a news report.

Microblogging site Twitter went offline for a while Friday after hackers calling themselves the Iranian Cyber Army apparently managed to change DNS records, redirecting traffic to another Web page.

Microsoft warned Thursday that hackers are actively exploiting a software vulnerability in PowerPoint, the company's presentation application.

Computers infected with the Conficker worm are being updated with a new variant that sidesteps an industry effort to sever the link between the worm and its hacker controllers, researchers at Symantec Corp. said Friday.

While CNN recently faced distributed denial-of-service attacks from Chinese hackers angry about the television network's coverage of a recent Chinese crackdown in Tibet, Chinese security officials remain worried hackers will strike while the Olympic Games are being held in Beijing.

A group of hackers calling itself "Anonymous" has hit the Church of Scientology's Web site with an online attack.

Apple Inc. CEO Steve Jobs said Tuesday that it's his company's job to stymie hackers who try to unlock the iPhone -- the first time the company has officially said it would fight attempts to use the popular device on unauthorized networks.

A new version of the Storm e-mail virus is populating blogs and online bulletin boards with links directing people to a Web site that is propagating the worm, representing a new mode of attack for hackers seeking financial gain, according to a security vendor that became aware of the virus Monday night.

Hackers have released attack code that exploits a critical vulnerability in Microsoft Corp.'s Word software -- the third such bug to be disclosed in the past week.

Hackers are distributing a file that they say lets users of the corporate version of Microsoft Corp.'s Windows Vista operating system get around the software's anti-piracy mechanisms.

As anyone who's ever held forth in a barroom debate can attest, strange topics attract strange people.

An exploit in Mozilla Corp.'s Firefox browser has been found that can hijack the software and monitor submit-and-click events.

Never mind worrying about hackers stealing your password. A security researcher with the Finnish military has shown how they could steal your fingerprint, by taking advantage of an omission in Microsoft Corp.'s Fingerprint Reader, a PC authentication device that Microsoft has been shipping since September 2004.

A design flaw in Windows XP and Windows 2003 systems with built-in wireless capabilities could be exploited by hackers to lure Wi-Fi users into connecting to malicious wireless networks, according to Microsoft Corp., which recently completed an investigation of the issue.