Operation BugDrop is a well-organized operation that employs sophisticated malware and appears to be backed by an organization with substantial resources. The malware uses PC microphones to bug targets and then sends the audio and other data files to Dropbox. The group infects victims using malicious Microsoft Word documents sent in phishing emails. CyberX researchers did not identify the clandestine hacking collective but said it was believed to be the work of highly skilled, government-backed nation-state hackers. The hackers spread the malware through emails containing malicious macros embedded in it.
Source: https://thehackernews.com/2017/02/ukraine-russia-hacking_20.html