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'Sustained' security challenge

In a report Monday, London-based RUSI said that as sanctions bite, the country has shown an increasing interest in virtual assets. It cited the alleged hijacking of crypto exchanges in South Korea as well as 2017's "WannaCry" global ransomware attack.

As a determined and sophisticated cyber actor in need of financial resources, North Korea is likely to continue to find ways of obtaining and exploiting cryptocurrencies. Royal United Services Institute

"North Korea has gone to extremes to raise funds and evade international sanctions, recently expanding these efforts to include the exploitation of cryptocurrencies such as Bitcoin," David Carlisle, a former official at the U.S. Treasury department's office of terrorism and financial intelligence, and Kayla Izenman, a financial crime and terrorist finance expert, wrote in the report. "As a determined and sophisticated cyber actor in need of financial resources, North Korea is likely to continue to find ways of obtaining and exploiting cryptocurrencies," they said in their report, "Closing the Gap: Guidance for Countering North Korean Cryptocurrency Activity in Southeast Asia." The WannaCry attack "signaled North Korea's interest in, and ability to exploit, cryptocurrencies," they said. And its cyber skills, coupled with the constant need for funds amid the squeeze of sanctions, point to the risk of a "sustained security challenge," they added. CNBC could not reach North Korea's foreign ministry for comment on Monday but the country has in the past vehemently denied allegations of cybercrime. In September, for example, the official Korean Central News Agency carried comments by a foreign ministry official denying involvement in the WannaCry attack, instead calling the United States the "chief culprit responsible for posing security threats in cyberspace."

Southeast Asia is vulnerable

Southeast Asia's growing virtual asset sector and lack of coordinated regulation present what Carlisle and Izenman called a "systemic risk" vulnerable to exploitation by North Korea, which they stressed has long used its countries to mitigate sanctions. "North Korean networks have engaged in fundraising and have evaded trade and financial restrictions through the use of front companies, agents and deceptive financial techniques at banks across the region," they wrote. "Because Southeast Asia is also host to a growing number of cryptocurrency businesses and users, countries in the region could prove vulnerable to North Korea's cryptocurrency-related activity as well," the report said.