Over 500 million PCs compromised by cryptocurrency mining script

Researchers revealed that over 500 million PCs were mining cryptocurrency without their users’ knowledge.
A team of researchers from AdGuard recently discovered that over 500 million users worldwide were mining cryptocurrencies without their knowledge. The mining script is thought to have been installed after affected users visited certain websites which had a mining software code operating in the background.

The researchers from AdGuard, a firm which primarily deals with ad blocking, discovered that over 220 popular and frequently visited websites with a large following were using crypto-mining scripts. The scripts started operating once an unsuspecting user opened up the website’s main page.

While the responsible websites enjoyed a worldwide following, most affected users seem to be located in the US. Approximately 18.7% of the sites who carried a covert mining software, came from the US.

To mine cryptocurrency, the mining software takes over a PC’s central processing unit (CPU), which is essentially the brain of a computer. By utilizing a portion of a computer’s CPU, the software is able to mine bitcoin. However, this process frequently negatively affects the computer's performance. Most users noted a significant and inexplicable slow-down caused by the mining script. According to the AdGuard researchers, the majority of websites who implemented mining scripts already had a “shady reputation”. Researchers have posited that the websites looked towards mining scripts to generate revenue, as their reputation prevented them from generating funds through more legitimate ways.

However, cryptocurrency mining software could soon become a mainstream practice amongst websites. The researchers warned that even though 220 affected sites may not seem like a significant threat, the size of their following is a reason for alarm. They used the example of Coinhive, since its launch on the 14th of September 2017, Coinhive has experienced rapid growth. In just a month, Coinhive has gone from zero to 2.2% of Alexa’s top visited 100,000 websites.

Their analysis illustrated the entire web. Currently, its considered a safe assumption to say that one in every forty websites employs a cryptocurrency mining script. Currently, the majority of mining scripts target Monero. So far, the estimated profit made from this particular mining script is estimated to be around $43,000. While the number may not be that high, it remains significant, considering that it was generated in a small amount of time and at zero cost.

The recent record highs experienced by cryptocurrencies has proven to be a lucrative incentive for questionable websites and cybercriminals to get a foot in the door. Many websites and hackers have started innovating new ways in order to profit from cryptocurrency mining software such as Coinhive and JSEcoin.

Currently, bitcoin remains the world's most valuable cryptocurrency and has an estimated market capitalization of almost $100 billion. This is set to reach even higher numbers, as the rumors of China reversing their bans continue to circulate in the industry.

Mining bitcoin is a process which includes confirming bitcoin transactions and adding the record into bitcoin's public ledger, which in turn generates new funds. This process requires a large amount of computer processing power. However other cryptocurrencies, such as Monero, has proved an alternative for easier mining. Websites have increasingly looked towards cryptocurrency mining scripts in order to generate funds, including The Pirate Bay, Showtime, and other prominent media downloading sites.