​Opera just added a Bitcoin-mining blocker to its browser

Finally, a browser is doing something to protect users from drive-by crypto-miners.
Written by Liam Tung, Contributing Writer

Norwegian browser maker Opera has launched the beta version of Opera 50, the first popular browser to integrate a built-in cryptocurrency-mining blocker.

The feature offers a new defense against the rise of cryptojacking or browser-based cryptocurrency miners that use a site visitor's CPU without gaining the owner's consent.

Crooks are increasingly hiding JavaScript miners on compromised websites and some have taken to deploying sneaky pop-under windows to continue using a CPU even after the victim has left the site, while groups using fake tech support scams have started integrating JavaScript miners into their bogus security-warning browser lockscreens.

"Your CPU suddenly working at 100 percent capacity, the fan is going crazy for seemingly no reason, and your battery quickly depleting might all be signs that someone is using your computer to mine for cryptocurrency," said Opera.


NoCoin blocks in-browser cryptominers

Image: Liam Tung/ZDNet

Opera's cryptocurrency mining protection is part of Opera's built-in ad blocker. The company has tried to differentiate itself with a range of novel features, such as the ad-blocker and a built-in VPN.

To enable the mining protection, users need to go to Settings or Preferences. The NoCoin (Cryptocurrency) setting can be found in Recommended lists of ad filters in the Block ads page.

"With NoCoin turned on, pages embedded with cryptocurrency mining scripts will be blocked in a similar way our mechanism blocks ads," said Opera desktop QA Kornelia Mielczarczyk.

In the beta at least, the NoCoin option is enabled by default. The feature works by blocking cryptocurrency mining scripts.

Related coverage

Android security: Coin miners show up in apps and sites to wear out your CPU

Expect to see more miners silently chewing up CPU resources through your browser.

Windows security: Cryptocurrency miner malware is enslaving PCs with EternalBlue

Stealthy and persistent cryptocurrency-mining malware is hitting Windows machines.

500 million PCs are being used for stealth cryptocurrency mining online

Your PC may be used to find cryptocurrency when you visit websites, with or without your consent.

Read more on Opera

Editorial standards