Cryptojacking is a relatively new threat on the Internet. It refers to websites abusing computing resources of visitors to mine cryptocurrency.

Internet users notice that something is wrong when the computer they use slows down to a crawl suddenly and when fans speed up in an attempt to cool down components of the device that get hammered.

The main issue with cryptojacking is that it is done behind the backs of users. Sites load cryptomining scripts on load to mine cryptocurrency using the resources of the computer of the user visiting the site. There is no opt-in process or information on what is going on.

Sites run these scripts to generate revenue. One of the advantages of running mining operations in the browser is that it happens in the background. It does not interfere with the site's layout or content.

Browser extensions may load crypto mining scripts as well. These work in the background just like scripts loaded by sites.

Cryptojacking Test

Opera Software was the first browser-making company that implemented anti-crypto mining protections in the browser natively.

While Opera was the first browser, content-blocking lists added cryptomining scripts before Opera did so.

Opera Software engineers created a site that you may visit to test whether you are protected against cryptojacking.

Visit the website and click on the start button on it to run the test. It won't take longer than a couple of seconds to complete and the result is either that the browser that you are using is protected or unprotected.

Opera Software displays aggregate ratings on the site as well. 73.6% of all users are protected from cryptojackingat the time of writing according to the statistics on the page.

Users who run browsers that are not protected have several options at their disposal to protect their browsers against crypto mining attacks.

  1. Use a browser extension that protects against JavaScript mining scripts.
  2. Use the Opera browser with ad-blocking enabled.
  3. Use a security software that protects against mining scripts.
  4. Install an anti-mining browser extension.
  5. Disable JavaScript on untrusted sites.

Closing Words

Opera tests the protection against a Coin Hive script only which leaves the possibility that the browser is vulnerable to these scripts. It is only a matter of time usually before new scripts or URLs do get blocked though.