AntiSec, part of the larger hacking organization Anonymous, disclosed information on officials and former officials who subscribe to Stratfor, which provides clients with analysis of national and international affairs. The data include e-mail addresses and other personal data, the Los Angeles Times reported Wednesday.
The disclosure could make it possible to impersonate Stratfor subscribers cyberspace, analysts told the newspaper.
John Bumgarner, an analyst at an independent non-profit research organization called the U.S. Cyber Consequences Unit, reviewed the data and told the Times the "exposure is huge."
He said the Stratfor data included e-mail addresses for about 19,000 members of the military, as well as 212 e-mail addresses associated with the FBI, 71 from the Pentagon's Defense Intelligence Agency, 29 from the National Security Agency and 24 from the CIA.
"We can assume that a foreign intelligence service has already taken advantage of this information," Bumgarner said.
Stratfor has taken down its Web site and said it is cooperating with investigators. AntiSec said it hacked Stratfor, in part, to demonstrate the service's poor security, the Times reported.