The Cambridge Cyber Summit

How investigators decide that a country is behind a cyberattack

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Increasingly, security experts don't just want to know how a cyberattack happens, but what country the attack is coming from.

Headlines about hacking incidents have become commonplace, particularly in the recent months leading up to the U.S. Presidential election. Whether it's breaches of voter registration systems, the Democratic National Committee, or the World Anti-Doping Agency, experts are feverishly trying to figure out who is behind the crimes.

More specifically, they want to know whether a sovereign state could be supporting those attacks. Lately, they especially want to know if it's Russia.

Experts say the WADA perpetrators were Russian hackers operating under the banner "Fancy Bear," with several U.S. officials pointing fingers at the Russian government specifically.

Moscow has repeatedly denied involvement with that group and other international cyberattacks.

So how do experts assess whether a country could be behind a hacking operation? It's often simple economics.

"I think that you can certainly make the argument that this group of repeat offenders, known as Tsar Team (Fancy Bear), is backed up by a government (allegedly Russian intelligence agencies), not only because of the substantial amount of money needed ... but also because of its level of coordination and sophistication," said Francesca Spidalieri, senior fellow for cyber leadership at the Pell Center for International Relations and Public Policy.

Russian hackers leak Simone Biles medical data
Russian hackers leak Simone Biles medical data

Other experts emphasize technological factors. Steve Grobman, CTO at Intel Security, told CNBC that a lot of the technology needed to execute an attack are available on the black market, for example, and are not necessarily all that expensive.

"A better indication of who an attack can be attributed to," he said, "comes when you actually get to take a look at things like the source code and can understand the level of sophistication something was built with."

Grobman's team analyzed a portion of the technical forensics associated with the World Anti-Doping Agency attack and concluded that there was insufficient evidence to definitively point the finger at the Russian government.

"We investigated the technical details that were publicly available around the WADA hacking case and compared them against other technical indicators and TTPs [tactics, techniques and procedures] we have gathered over the years," he said. "The amount of available technical details combined with some similar TTPs are not enough evidence in our opinion to attribute this campaign to a certain group or state-sponsored operation."

Scott Borg, director and chief economist at U.S. Cyber Consequences Unit, an independent, non-profit research institute, told CNBC that he's confident the attack was carried out by Russian groups tasked with spreading Russian President Vladimir Putin's political and military agenda.

"This is as certain as anything can ever be in the cyber realm," he said.

The power of computers and of a single determined individual to be able to cause great harm, even if they are not well-financed, is pretty astonishing.
Matthew Prince
CEO, CloudFlare

Borg said the Russian government maintains close relationships with many hacker groups, and said it has a history of other cyber-attack campaigns designed to influence political outcomes, particularly in Eastern European countries.

Russia is widely blamed for a broad campaign of cyberattacks against Estonia in 2007, though some experts still question whether there's enough evidence to connect the Kremlin to that attack.

"The hacker groups that the Russian government employs to do its bidding range from consulting groups regularly hired by the Russian government to criminal enterprises with which the Russian government only has slight, arms-length contact," Borg said.

Borg cautioned, though, that just because he believes a nation state was responsible for these attacks does not mean infiltrating the systems themselves required the resources of a country's government.

Matthew Prince, CEO of internet security firm CloudFlare, told CNBC he is skeptical about claims that the Russian government is funding the latest spate of hacks.

"The power of computers and of a single determined individual to be able to cause great harm, even if they are not well-financed, is pretty astonishing," he said.

The bottom line, said Bruce Schneier, security expert and CTO at Resilient, an IBM company, is that in terms of figuring out who's really behind a hack, "it's incredibly complicated."

"We do the best we can, but it's not great," Schneier said. "Attribution is just hard in cyber space."

—CNBC's Harriet Taylor contributed to this report.