BALTIMORE — The recent leak of national security documents would have been easier to discover and prevent had the U.S. Department of Defense already instituted the latest cybersecurity practices known as zero trust, according to Pentagon Chief Information Officer John Sherman.

The disclosure of the classified reports, allegedly spearheaded by a 21-year-old member of the Massachusetts Air National Guard, has prompted a hard look at the department’s information-security practices. The breach included insights about the ongoing Russia-Ukraine war.

Sherman on May 3 said a zero-trust approach “sure as heck would’ve made it a lot more likely that we would have caught this and been able to prevent it at the front end.” Prying eyes and ears are both an external threat — considering China, Russia and other nations — and an internal hazard.

“This is something we’ve grappled with for years,” Sherman said at the AFCEA TechNet Cyber conference in Baltimore. “We had the Snowden disclosures nearly 10 years ago. We’ve had other unfortunate events here.”

Edward Snowden was a former American intelligence contractor who in 2013 made public the existence of global surveillance dragnets. The U.S. government deemed him a traitor; he was later granted Russian citizenship.

Zero trust is a different paradigm for cybersecurity, one which assumes networks are always at risk or already jeopardized, requiring constant validation of devices, users and their digital reach. Sherman previously likened zero trust to believing “no one or no thing.”

The Pentagon in November published its transition strategy, with eyes set on widespread implementation by fiscal 2027. Defense officials have said the timeline is challenging but doable.

Sherman’s remarks at the AFCEA conference echo those made by Navy Chief Technology Officer Don Yeske, who in April told C4ISRNET the tenets of zero trust would have aided the department detect suspect behavior.

“You begin from the point of assuming your network has been compromised, and if it hasn’t been compromised, that compromise is inevitable,” Yeske said at the virtual C4ISRNET Conference. “Insider threats light up like a Christmas tree when that is your approach.”

The Pentagon last month announced it would conduct a comprehensive review of its policies and procedures. Sherman and Ronald Moultrie, the undersecretary of defense for intelligence and security, among others, are involved.

Initial results of the audit are expected within 45 days.

C4ISRNET reporter Courtney Albon contributed to this article.

Colin Demarest was a reporter at C4ISRNET, where he covered military networks, cyber and IT. Colin had previously covered the Department of Energy and its National Nuclear Security Administration — namely Cold War cleanup and nuclear weapons development — for a daily newspaper in South Carolina. Colin is also an award-winning photographer.

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