Bitcoin mining software is exploiting the computers and smartphones of visitors to popular websites, according to a report.
Researchers discovered that websites including Showtime and the torrenting site The Pirate Bay were among those containing a tool that hijacks the computing power of visitors to generate bitcoin and other cryptocurrency.
The bitcoin mining software, which is invisible on a surface level to the sites’ visitors, has led cybersecurity firm Cloudflare to block sites that use it, TorrentFreak reports.
The software can be loaded to a website by hackers, as appears to be the case with Showtime, or it can be loaded intentionally by the site’s owner to generate revenue.
One site that used mining software intentionally was ProxyBunker.online, a site that links to streaming and torrenting websites. The owner of the site told TorrentFreak that its website was blocked from using Cloudflare services as a result of running a cryptocurrency miner.
“Multiple domains in your account were injecting Coinhive mining code without notifying users and without any option to disabling the mining,” wrote Justin Paine, head of trust and safety at Cloudflare.
“We consider this to be malware, and as such the account was suspended, and all domains removed from Cloudflare.”
One of the most popular tools being used to secretly mine cryptocurrency is Coinhive, which mines for the bitcoin-like virtual currency Monero.
Coinhive was the chosen tool of The Pirate Bay, who was criticized for not warning visitors to its site that it was using the software. The file-sharing site posted a statement last week saying that the Monero miner was only a test.
The technique of hijacking users’ web browsers to mine cryptocurrency, referred to as “cryptojacking” by some experts, appears to be more popular for newer cryptocurrencies that contain features that are untraceable to law enforcement.
Mining bitcoin—the process of confirming bitcoin transactions and adding their record to bitcoin’s public ledger in order to generate new units of the currency—requires vast amounts of computing power, however newer cryptocurrencies with lower market value are easier to mine.
Hackers are also hijacking devices connected to the so-called Internet of Things, such as smart fridges, toasters and light bulbs.
Earlier this year, IBM researchers discovered a bitcoin mining component in the Mirai botnet—a form of malware that exploits security vulnerabilities to take control of IoT devices.
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