Two Italian researchers from the University of Padua have compiled an estimate of how much money, in Bitcoin, has been generated by the various types of ransomware used by cyber-criminals.
The researchers believe about US$ 4.6 million (£3.3 million) has been paid in Bitcoin since 2015, although there is another US$ 45 million (£32 million) that is associated with known ransomware Bitcoin wallets for which they can't quite account, reported the MIT Technology Review. The researchers only looked at bitcoin payments since exchanges made in this currency are public.
CryptoWall, which first came on the scene in June 2014 according to Symantec, by far generated the most income for its creators bringing in about US$ 2.2 million (£1.6 million). CryptoLocker was second garnering about US$ 500,000 (£358,000) followed by DMA Locker, US$ 178,000 (£127,400); WannaCry, US$ 86,000 (£61,553); CryptoDefense US$ 64,000 (£45,811), NotPetya, US$ 9,800 (£7,014) and KeRanger, US$ 4,200 (£3,006).
MIT reported that the Padua team also looked at the well-known ransomware types TelsaCrypt and KillDisk, but discovered these made little or no money.
The methodology used to break out the ransom included creating a database of bitcoin accounts associated with this kind of activity since 2013 when CryptoLocker first appeared.
“We found twenty ransomware that fulfilled our selection criteria, ie, those ransomware: (i) that used Bitcoin as at least one mode of ransom payment, and (ii) for which at least one Bitcoin address is publicly known,” MIT said.