"Nevertheless, the DDoS threat landscape continues to evolve. While cyber extortion has been around for quite some time, the adoption of Bitcoin as a method of ransom will continue to attract new miscreants into the DDoS space," the Recorded Future report concluded.
Speaking with CNBC, Bradshaw said he thought the anonymity commonly associated with cryptocurrencies (of which bitcoin is the most popular) "is pretty enticing" for those considering cyber extortion. Earlier schemes relied on bank accounts or money orders, he said, so criminals felt they were at greater risk of being tracked down by authorities.
Bitcoin, however, is not even remotely an anonymous system. Law enforcement agencies have on multiple occasions traced bitcoin transactions to criminals. Famously, former FBI Special Agent Ilhwan Yum traced 3,760 bitcoin transactions from servers tied to the investigation of illicit online marketplace Silk Road to the laptop of Ross Ulbricht.
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In part on the basis of this testimony, a Manhattan court found that Ulbricht had been the mastermind behind the Silk Road, and consequently found him guilty on seven counts — including being a "drug kingpin." He was sentenced to life in prison.
That cautionary tail has not stopped some criminals from using the digital currency in brazen attacks such as those by DD4BC and the Armada Collective.
"Perhaps that might be something that might be a little misunderstood," Bradshaw said of authorities' bitcoin tracing capabilities. Still, he said, the relatively minimal barriers to entry and the lack of personally identifiable information tied to bitcoin addresses make it appealing to hackers.