Truesec cybersecurity experts: Maybe the first one sold its TTPs to the ransomware gang, probably they are closely affiliated and may be part of the same network.
The bait is the usual invoice, theoretically contained in the compressed attachment. Inside there is an exe file which, when opened, triggers the infection of the malware.
The lure is a fake CV attached in a mail. If the victim opens it, it asks to install the reader. Meanwhile Meanwhile, a JS activates the malware infection chain.