The Senate pulled its Web site after being defaced yesterday at 4:53 PDT, a Senate spokesperson confirmed today. Only the public Web site was compromised, according to the Senate; other systems, such as email, remained intact. The FBI is participating in the Senate's investigation into the attack.
"Our technical staff has been working since the incident occurred to resolve the problem," said Senate spokeswoman Sherry Little. "We will restore the Web site as soon as we can protect it and prevent a recurrence."
The FBI had troubles of its own Wednesday and had to pull its site after suffering a denial-of-service attack. The FBI site remained down at midday today while the agency evaluated the system for the second day running.
"The security of the system was fine, and no one got into it," FBI spokesman Frank Scafidi said yesterday. "But because of the attack it got so clogged we had to pull it."
The Senate and FBI suffered different kinds of attacks. The Senate site was defaced, which means hackers accessed the system and altered the Web site. The FBI suffered a denial-of-service attack, in which attacking computers coordinated a series of requests that overwhelmed the server's capabilities, effectively shutting it down.
Earlier yesterday the FBI mistakenly characterized its attack as an intrusion attempt.
Some computer security analysts tied FBI attack to recent actions by the Houston division of the FBI against suspected criminal hackers in Houston. The Houston FBI said it confiscated a number of computers yesterday prior to the Web site attack.
"We were conducting an ongoing investigation regarding computer intrusions," said Houston FBI spokesman Ronaldo Moss. "We did search warrants on residences here in Houston and confiscated some computers."
The battle between malicious hackers and the government has escalated sharply in recent months.
The Defense Department, for example, this year confirmed that its computer systems have been under constant attack from sources at home and abroad and that it has been stepping up its efforts to defend those systems.
The White House also has been targeted.
One security analyst said the attacks against the government are coming from a widely dispersed group of young hackers, rather than any one organization.
"This is part of a mass reaction of people who seek protection in numbers," said Alan Paller, director of research for the SANS Institute (System Administration, Networking, and Security Institute). "In this case there's such a long-term animosity against the government. There's a whole ethic that the people trying to protect computer systems are bad people."
Paller said the Houston computer confiscations and another round by the Seattle FBI sparked a reaction that spread beyond those areas. The attackers are "literally children," Paller said, many younger than 16 years old.
News of the FBI's Web site outage was first reported by online computer security news and information site AntiOnline.
AntiOnline posted a mirror of the Senate hack, which the Senate confirmed as authentic.