Phishing emails purporting to contain COVID-19 safety information from the World Health Organization (WHO) are instead phishing lures intended to spread a novel remote-access Trojan (RAT) called Nerbian.

A team of Proofpoint researchers have published a report noting that so far, the Nerbian RAT, first spotted on Apr. 26, has spread primarily throughout Italy, Spain, and the UK. Notably, Nerbian is written in the Go language, taking advantage of several open source libraries, the analysts added. 

The RAT leverages multiple anti-analysis components and has cyber espionage modules for keylogging and screen grabs, researchers said, in addition to typical backdooring functionality. 

Nerbian got its name directly from the malware code, the researchers explained, which references the name of a fictional place from the novel Don Quixote.

"Malware authors continue to operate at the intersection of open-source capability and criminal opportunity,” Sherrod DeGrippo, vice president of threat research and detection at Proofpoint, told Dark Reading in an emailed statement.