Campaign PCs of Obama, McCain cyberattacked

Last summer, Sen. Barack Obama's presidential-campaign computers came under cyberattack from an "unknown entity." His machines weren't alone; John McCain's computers were also attacked, according to a report appearing Wednesday on the site of Newsweek magazine.

The Obama attack was initially thought to be a piece of malware downloaded from a phishing site. Newsweek reports that "the next day, both the FBI and the Secret Service came to the campaign with an ominous warning: 'You have a problem way bigger than what you understand,' an agent told them. 'You have been compromised, and a serious amount of files have been loaded off your system.'"

The McCain campaign's computer system was also compromised over the summer. Newsweek confirmed with a top McCain official that the FBI had become involved. A federal investigation into both attacks is under way.

According to Newsweek Editor at Large Evan Thomas, the FBI and White House officials told the Obama campaign that a foreign entity or organization was likely responsible, not political opponents. Independently, Obama technical experts have speculated that the hackers were Russian or Chinese. The files accessed appear to be policy-related and thus potentially useful in future negotiations with a new presidential administration.

Earlier this year, during the primaries, an online prank had the Obama campaign site redirected to Sen. Hillary Clinton's campaign site.

The Newsweek report is part of a special edition that will be on newsstands November 6 through 16, and online November 5 through 7.