Cryptojacking is a new phenomenon, which was popularized by ThePirateBay embedding its website with a Javascript-based crypto-currency miner. It quickly sprung up the debate on whether crypto-currency miners hidden into web-pages could become the revenue model of the future, replacing online advertising or paid subscriptions. Some commentators argue that it's fine as long as users are made sufficiently aware that a website is embedding a miner, and is presented with a choice between ads and the miner. Others were steadfast against the idea as heavy Internet browsing (across multiple tabs), could bring down computers to a crawl, and have a more than tangible impact on electricity bills.

According to an ArsTechnica report, there could be at least 2,500 websites out there, with embedded crypto-currency miners that are hidden from the users. Willem de Groot, an independent cybersecurity researcher told the publication that he estimates JS miners may have proliferated to 2,496 websites, and its adoption is on the rise. Some dishonest websites embed miners as a revenue source in addition to ads and sponsored content. At the heart of the controversy is Coinhive. This company sells easy-to-integrate crypto-currency miners that can be embedded into websites as a revenue source. The company is on a marketing overdrive, writing to siteops and bloggers to spread their miners.The softest targets of Coinhive appear to be Wordpress blogs that are struggling to make money off cheap ads. This is a troubling trend because blogs that don't disclose running embedded miners risk reducing the credibility of the blogging platform they're based on (Wordpress, Blogger) as a whole, readers would avoid emerging blogs as they'd fear running into hidden miners.

Making matters worse, neither Google, nor Mozilla, have come up with anti-miner measures built into Chrome or Firefox. Ad-block Plus, the popular browser extension that disables web ads, introduced a feature that disables scripts that exhibit mining behavior, with a nascent degree of heuristics. You can also install this Chrome extension to weed-out Coinhive scripts. The more experienced users among you can edit your Hosts file to nullroute Coinhive. Popular anti-virus vendors such as Kaspersky and McAfee, which include anti-phishing features with their software, have set out to identify and block sites with embedded miners.