Swift cyberattacks a big deal: Fmr. Treasury official

Banks' vulnerabilty to cyber hacks

The global financial messaging network Swift is critically important to the world's financial system and the recent cyberattacks on the institution are "worthy of freaking out" about, former Treasury Department official Tony Fratto said Friday.

Swift warned Thursday of a second malware attack similar to the one that led to February's $81 million cyberheist from a Bangladesh central bank account at the New York Federal Reserve Bank.

"You don't usually hear about $81 million bank heists," he said in an interview with CNBC's "Power Lunch."

"Those are big numbers any way you cut it and it would be a significant hole for lots of banks."

SWIFT says commercial bank hit by malware attack like $81M Bangladesh hack
Hackers vs. banks battle heats up

Fratto, a CNBC contributor and advisor to all three Treasury secretaries under President George W. Bush, has been to Swift's headquarters. He called it the plumbing of the global banking system, handling billions of transactions between 200 countries.

While it takes security very seriously, Fratto said it is vital Swift fix its security problems.

"This is a different world" than when the institution first started decades ago, he said. "Where the money is, is where the risk is and they have to be one step ahead of the cybercriminals."

The second attack targeted an unnamed commercial bank. Swift said the assailants exhibited a "deep and sophisticated knowledge of specific operational controls" at targeted banks and may have been aided by "malicious insiders or cyber attacks, or a combination of both."

— Reuters and CNBC's Kerima Greene contributed to this report.