Nerbian Rat is a complex malware with low complexity obfuscation, that was designed to affect as many systems as possible. Coded in OS-agnostic ‘Go’, it was designed to evade detection from security tools. It has anti-analysis and anti-reversing capabilities. It appears that the malware authors invested significant technical effort into creating the malware (maldoc phishing lure + dropper w/ anti-VM & anti-reversing checks + encrypted config file + etc. etc.) yet they did not employ obfuscation beyond packing the sample with UPX.