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Your PC could be crypto-mining right now… and you wouldn’t even know

Even if you don't want to mine for cryptocurrencies some websites you visit might have your PC doing it anyway.

Drive-by crypto-mining

Everyone wants to mine for cryptocurrency, right? It’s free money after all… so long as someone else pays for the electricity anyways. You might even be mining this very minute. Though not necessarily through choice, or in any way that will net you some cash. This is extreme drive-by crypto-mining!

Forget mining, these are the best CPUs for gaming.

Some dodgy websites you might visit could pop-up asking whether you wish to support their various nefarious practices through letting them pool your hardware resources, while on their page, to help them mine cryptocurrencies. Some inscrutable sorts won’t ask, while some new ones won’t ask and will continue to piggyback your CPU juice even once you’ve closed your browser window.

Researchers over at Malwarebytes have discovered a technique which hides a pop-under window out of sight below your taskbar’s clock. This hidden window will remain open until you kill your browser through Task Manager, or some such special not-just-pressing-the-X-button-to-close measures. Which is what this gif from Malwarebytes’ blog post demonstrates.

Malwarebytes hidden mining demo

This stealth window isn’t suddenly going to spin up your graphics card to start mining Ethereum, but it will grab a portion of your CPU hardware to calculate the maths needed to mine for other more processor-focused currencies such as Monero. Generally the code will ensure the CPU doesn’t run maxed out to ensure that it isn’t discovered by the end-user immediately.

And it just sits there, taking your power and not given anything back. How rude. And since it’s not strictly an ad it won’t get blocked by your adblocker, or picked up by any other security software. The only way to catch it seems to be resizing your taskbar to make it pop up, or potentially by remaining vigilant with a transparent taskbar.

So, beware.