By Danny Yadron in San Francisco and Siobhan Gorman in Washington 

Earlier this year, investigators for Silicon Valley security company FireEye Inc. visited a U.S. firm to determine who, and what, sneaked into the firm's network harboring military secrets.

There they found what they call a sophisticated cyberweapon, able to evade detection and hop between computers walled off from the Internet. The spy tool was programmed on Russian-language machines and built during working hours in Moscow. FireEye's conclusion, in a report to be released Tuesday: The cyberspying has a "government sponsor--specifically, a government based in Moscow."

The report is one of four recent assessments by cybersecurity companies, buttressed by reports from Google Inc. and U.S. intelligence agencies, pointing to Russian sponsorship of a skilled hacking campaign dating back to 2007. Targets included NATO, governments of Russia's neighbors, and U.S. defense contractors Science Applications International Corp. and Academi LLC, the U.S. security firm previously known as Blackwater.

Collectively, the new research offers evidence supporting a view long expressed privately by U.S. officials and American security researchers: Moscow commands the A-team of Internet adversaries.

China, the object of recent U.S. allegations of cyberspying, may hack more often, U.S. officials and researchers say. But Russia hacks better.

"I worry a lot more about the Russians" than China, America's top spy, Director of National Intelligence James Clapper, said at a University of Texas forum this month, speaking of cyberattacks.

A U.S. official said differentiating between Russian criminal hackers and government hackers is difficult because the government uses cybersurveillance tools created by criminal groups and criminals use tools developed by the government.

For example, U.S. officials still haven't determined whether the high-profile infiltration of a classified military system in 2008 was carried out by criminals or government hackers because the same surveillance tool was used by both, the U.S. official said.

More recently, the infiltration of J.P. Morgan Chase & Co. has also been difficult to pin down.

"It looks to be criminal and of Russian origin," the U.S. official said. But when it comes to gauging whether that criminal element is working with the government, "you're back into that gray area. You really can't tell."

People with direct knowledge of the investigation said there is no evidence implicating the Russian government in the J.P. Morgan breach.

The Russian embassy didn't respond to a request for comment.

American complaints about Moscow's espionage skills come as U.S.-Kremlin relations have hit a post-Cold War low following Russia's incursion into Ukraine. Although some security firms said they are seeing more activity from Russia-linked attacks these days, U.S. officials say it's difficult to establish a baseline for Russian-based cyberspying and that finding such attacks is "serendipitous."

FireEye shared its findings earlier this month with The Wall Street Journal, which then found that other security firms and the U.S. government had reached similar conclusions. FireEye also has shared its findings with the government. "Who else benefits from this?" asked Laura Galante, a FireEye manager and former Russia analyst for the U.S. Department of Defense. "It just looks so much like something that comes from Russia that we can't avoid the conclusion."

FireEye's Mandiant unit made a name for itself in 2013 when it revealed a Chinese-military hacking group working from an office building in Shanghai. The Justice Department confirmed many of Mandiant's findings, even naming one of the same hackers, in May when it charged five People's Liberation Army officers with stealing U.S. trade secrets. FireEye acquired Mandiant for $1 billion in January.

In the case of the Russian-language hackers, researchers inside and outside the government compared notes and believe they are tracking the same group. They dubbed the spy tool described by FireEye "Sofacy."

The company's investigators said they were caught off guard when they responded to the U.S. firm that had been hacked earlier this year and which held military secrets. The company, which they decline to name, had lost sensitive data, but there were none of the digital fingerprints that Chinese hackers often leave behind, investigators said. Rather, the malware, or malicious code, was littered with spycraft.

The malware program also deployed countermeasures to deter investigators from determining how it worked. It encrypted stolen data and exported it in a way to resemble that victim's email traffic to better conceal it. FireEye analysts determined the group has been active since at least 2007 and has steadily updated its hacking tools.The malware's authors also designed it, if needed, to harvest data from machines not connected to the Internet by jumping onto USB thumb drives.

Governments often disconnect computers with highly sensitive information to guard against cyberspies. But government spies in the U.S. and elsewhere have used USB drives to overcome this defense in the past. The Russian hackers used this technique in the 2008 Defense Department intrusion, U.S. officials have said. "These are state-grade weapons," Ms. Galante said.

Sofacy's authors consistently logged changes to the code between 8 a.m. and 6 p.m. local time in Moscow and St. Petersburg--like an analyst working at a desk, Ms. Galante said. Most of their computers were configured to use Russian, researchers at FireEye and Google found.

Perhaps most telling, researchers say, the hackers deployed the malware almost exclusively in targets of interest to Russia--government networks in the Caucasus and Eastern Europe, U.S. defense contractors and NATO. FireEye found a well-crafted phishing email aimed at a Georgian journalist, purporting to come from an editor at libertarian magazine Reason.

In another phishing attack, the security firm Trend Micro Inc. found the group created fake websites designed to trick employees at Academi into handing over their work email credentials, Tom Kellermann, chief cybersecurity officer said. One of these sites, the slightly misspelled academl.com, was created just weeks after the Russian government accused a firm with links to Academi of sending freelance troops to Ukraine to support the government, according to Internet registration records.

Academi has denied any involvement in Ukraine. A spokeswoman declined to comment.

Trend Micro said the hacking group aimed similar techniques at Science Applications International. A SAIC spokeswoman said the company appeared to have been targeted by hackers creating fake company websites, but blocked the efforts.

Two other computer-security firms with close ties to federal law enforcement, Crowdstrike Inc. and iSight Partners Inc., dubbed the hackers behind the Sofacy malware "Fancy Bear" and "Tsar Team," respectively. Executives at both companies acknowledge the names are references to Russia.

The Google researchers don't name Russia explicitly in its researchers' previously unreported memo submitted last month to the Department of Homeland Security and other security professionals. Rather, the 41-page white paper, viewed by the Journal, referred to the hackers as a "sophisticated state-sponsored group" and noted the computers used to craft the cyberweapons were set to work with the Russian language. A Google spokesman confirmed the report's existence and contents.

Write to Danny Yadron at danny.yadron@wsj.com and Siobhan Gorman at siobhan.gorman@wsj.com

Subscribe to WSJ: http://online.wsj.com?mod=djnwires

Alphabet (NASDAQ:GOOG)
Historical Stock Chart
From Mar 2024 to Apr 2024 Click Here for more Alphabet Charts.
Alphabet (NASDAQ:GOOG)
Historical Stock Chart
From Apr 2023 to Apr 2024 Click Here for more Alphabet Charts.