The remote access trojan mimics legitimate computer activity to make it harder to detect, the researchers said.

The hackers are exploiting businesses' reliance on digital updates from the federal government.

The hackers could be prepositioning for a retaliatory attack, or biding their time to collect intelligence, researchers say.

Hackers are trying to spread malicious software by using world leaders' names to generate interest.

Remcos is sold by a German company, Breaking Security, that markets it as a legitimate way to remotely access computers.

As well-crafted hacking tools become more ubiquitous, long simmering rivalries between developing nations take on a new dimension: cyber espionage runs rampant.

RiskIQ and Proofpoint's findings reveal not only newly discovered, highly sophisticated tactics and capabilities held by North Korea's Lazarus Group, but they also highlight the internal divisions…

"It is highly likely that this tool will continue to be uncovered as part of targeted attacks for some time."