North Korea has denied accusations made this week by the US government that it was behind the WannaCry ransomware outbreak in May.
North Korea claimed that Washington was engaged in a campaign to "demonise" the country by accusing it of being behind the malware, which affected more than 300,000 computers across the world in May. The NHS was particularly badly affected, largely due to lackadaisical patch management by NHS trust IT departments.
The malware was able to self-propagate by exploiting a flaw in Microsoft's implementation of the SMB networking protocol. The flaw had been used for years by the US National Security Agency (NSA) for its own ends, but was published at the beginning of the year after a trove of NSA exploits was leaked.
But according to a spokesman from North Korea's foreign Ministry, the US has made "absurd" allegations against the country and denies the claims completely.
The North Korean government claims that Washington has "ulterior motives", saying: "As we have clearly stated on several occasions, we have nothing to do with cyber-attacks."
"This move is a grave political provocation by the US aimed at inducing the international society into a confrontation against the DPRK [Democratic People's Republic of Korea] by tarnishing the image of the dignified country and demonising it."
Britain has also accused North Korea of being behind WannaCry. On Tuesday, the Foreign Office said: "The indiscriminate use of the WannaCry ransomware demonstrates North Korean actors using their cyber programme to circumvent sanctions."
North Korea, though, has long been accused of being involved in various illegal activities, such as counterfeiting and the production of narcotics, often using its diplomatic network to distribute forged currency and even drugs. These activities, it is claimed, are directed from the very top by an organisation called Central Committee Bureau 39 of the Workers' Party of Korea, or simply Room 39.
In 2014, North Korea was accused of being behind a devastating compromise of Sony Pictures Entertainment.
At the time, experts believed that North Korea was retaliating over a film called The Interview, which involved a plot to assassinate North Korean leader Kim Jong-un.
Security researchers are able to link cyber attacks and, hence, attribute attacks to particular groups by examining the code, tools and techniques used, and identifying common themes.
North Korea has also been sanctioned (again) over the country's nuclear testing programme and development of weapons of mass destruction.
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