Five people from South Korea have been taken into custody following claims that they placed cryptocurrency malware on the computers of thousands of people.
The malicious software, which is believed to be related to crypto mining, is said to have found its way on to more than 6,000 computers.
According to police in the country, 32,435 email messages with the computer malware incorporated into them were sent out by a group of men – allegedly led by a 24-year-old man named Kim Amu-gae.
The malware was concealed within what appeared to be a document, sent as an email attachment. Once opened, the malware was activated and illegitimate mining activities began on the affected computer.
It is believed that the alleged victims were found on recruitment websites, and they are suspected to have used databases containing information about applicants for job roles at technology firms.
One report in the international cryptocurrency media suggests that those behind the hackings pretended to be potential employers.
However, there were some positive reports out of the case. Many of the alleged victims are believed to have had sufficient anti-virus software installed on their computers, and hence were largely unaffected.
In total, it is believed that the alleged hackers were only able to make about $1,000 out of the scam.
A statement from the South Korean police emphasised the role of anti-virus software providers in preventing problems.
“Because cybersecurity firms and anti-virus software operators responded quickly to the distribution of mining malware, the group of hackers were not able to generate a significant revenue from their operation”, the statement read.
“In most cases, anti-virus software detected the malware within three to seven days. If the malware was detected, the hackers sent new malware, but it was detected again by anti-virus software.”
Police also took the opportunity to remind computer users that anti-virus software is a wise move.
“Crypto jacking significantly reduces the performance of computers and if exposed to institutions, it could have a serious effect on the society”, they said.
“PC users must have secure anti-virus software in place and update browsers frequently. Also, if the performance of a computer suddenly drops, users will have to suspect the presence of mining malware.”
South Korea is a highly developed country with a strong technology scene, which makes its citizens ripe targets for cryptocurrency scams.
Earlier this year, for example, a bizarre case involving an alleged crypto scam surfaced in the South Korean media.
In that case, a firm called Shinil Group claimed that it had discovered an old Russian ship. The Dmitrii Donskoi, which went underwater more than a century ago, was described by the firm as being worth over $100 billion US dollars due to the gold it contained.
In exchange for buying cryptocurrency from the firm, Shinil offered to send buyers gold extracted from the sunken ship. Despite the firm making a significant amount of money from investors, however, its CEO Choi Yong-seok later said that there was no significant evidence that the ship was valuable.