The White House acknowledged Tuesday that the unclassified computer systems at the U.S. presidential mansion were vulnerable to hackers.
Ben Rhodes, a deputy national security adviser, made the remarks in response to media reports that Russian hackers got access to some sensitive White House information, such as President Barack Obama's private schedule.
Rhodes would not confirm that sensitive information had been accessed, nor would he comment on where the threat originated. But, he said, "There's always vulnerability,'' which is why the White House operates a separate, secure system for classified data.
"We have classified systems that are secure and we take regular precautions to secure our own classified networks as well. I think we were very up front in acknowledging a cyber intrusion last year, so that is not new. We don't talk about where cyber intrusions originate from because we are constantly taking actions to prevent them," Rhodes told reporters.
The U.S. government has been hit by several cyberattacks, including the hacking of unclassified computers at the White House and State Department, as well as the Twitter and YouTube accounts of U.S. Central Command, which oversees the military campaign against Islamic State militants in Iraq and Syria.
Who's to blame?
Some of the attacks have been blamed on hackers in Russia, China and North Korea.
Earlier this year, the White House announced the creation of a federal agency to analyze threats to the nation's cybersecurity and determine strategy to combat them.
The Cyber Threat Intelligence Integration Center will coordinate cyber threat intelligence from the Federal Bureau of Investigation, the National Security Agency, the Department of Homeland Security and other federal agencies. The center will operate under the guidance of the director of national intelligence.