"Outraged" after his personal email account was hacked and documents deemed classified were released by WikiLeaks, CIA Director John Brennan today said the cybersphere poses the "most-dangerous" threat to the US.
"Cyber-front worries me at night," Brennan said.
Brennan spoke about the issue for the first time since the whistle-blower website began publishing the documents, which appear to date back to 2007-09, when he worked in the private sector.
"The hacking (of my personal AOL account) shows just how vulnerable people are to those who want to do harm," he said.
Top American intelligence officials, who made a rare collective appearance at a conference co-sponsored by the CIA at George Washington University, said such a threat comes from both the state and the non-state actors.
Brennan said the threat to cyberspace come from "those sub national actors who can do tremendous harm."
He said cybersphere poses the "most dangerous" threat to the US. "The vulnerabilities are there," he said.
On Wednesday, WikiLeaks began publishing documents from "Brennan's non-government email accounts".
Among the emails released were his personal information and views on Pakistan and Afghanistan. Also included was a draft on national security challenges said to have been created in 2007.
"I was certainly outraged. I was certainly concerned," Brennan said. "I was dismayed by how some of the media handled it."
Admiral Mike Rogers, Commander US Cyber Command; Director, National Security Agency (NSA), and Chief, Central Security Service said that there are many state actors who are planning to do harm to the US.
Rogers said "it is the best and the worst of time."
Doug Wise, Deputy Director, Defence Intelligence Agency (DIA), said that cyberspace is a great equaliser, but this also provides state and non-state actors to target the US "at a lesser cost."
"One of the risk of being a senior intelligence official is that you make yourself a target," he said.
Brennan said crisis can arise instantly in the age of social media. Arab Spring "has totally transformed" the social, political landscape of the Middle-East, he said.
