UK Cyber Security Division Issues Warning on PC 'Cryptojacking'

The UK National Cyber Security Centre highlighted the rising number of browser apps which force computers to mine cryptocurrencies in a new report.

AccessTimeIconApr 10, 2018 at 6:00 p.m. UTC
Updated Sep 13, 2021 at 7:48 a.m. UTC

Cryptojacking - the act of hijacking a user's computer to mine cryptocurrencies - is likely to "become a regular source of income for website owners," a British government agency warned Tuesday.

The U.K.'s National Cyber Security Centre, the technology wing of the Government Communications Headquarters, highlighted cryptojacking as a "significant" concern in its latest "cyber threat to UK business" report.

In particular, the report singled out websites which mined cryptocurrencies without users' permission, noting that 55 percent of businesses worldwide suffered from cryptomining attacks last December. The report specifically referred to monero, which has frequently been mined through browser application Coinhive, as one example.

Nor have the attacks waned in 2018. The report noted that more than 4,000 websites secretly mined a cryptocurrency using a plugin for visually-impaired users. The report noted that "the only way users may notice their devices are being cryptojacked is a slight slowdown in performance."

The document continued:

"The technique of delivering cryptocurrency miners through malware has been used for several years, but it is likely in 2018-19 that one of the main threats will be a newer technique of mining cryptocurrency which exploits visitors to a website."

The agency added that "we assume the majority of cryptojacking is carried out by cyber criminals, but website owners have also targeted visitors to their website and used the processing power of visitors’ CPUs, without their knowledge or consent, to mine cryptocurrency for their own financial gain."

That being said, some sites may mine cryptocurrencies with their users' permission, the report noted, citing Salon as an example. The publication announced in February that it would let its readers choose between advertisements and cryptocurrency mining in order to access its content, as previously reported. However, the report noted that this was only a trial.

The report advised users to use ad blockers and anti-virus programs which include browser mining blocks to prevent their computers from being hijacked.

Monero image via Sharaf Maksumov / Shutterstock


Please note that our privacy policy, terms of use, cookies, and do not sell my personal information has been updated.

CoinDesk is an award-winning media outlet that covers the cryptocurrency industry. Its journalists abide by a strict set of editorial policies. In November 2023, CoinDesk was acquired by the Bullish group, owner of Bullish, a regulated, digital assets exchange. The Bullish group is majority-owned by; both companies have interests in a variety of blockchain and digital asset businesses and significant holdings of digital assets, including bitcoin. CoinDesk operates as an independent subsidiary with an editorial committee to protect journalistic independence. CoinDesk employees, including journalists, may receive options in the Bullish group as part of their compensation.