What is cryptojacking? – Microsoft 365 (2024)

Microsoft 365 Life Hacks > > What is cryptojacking?

June 27, 2024

Between people trying to scam your grandparents, steal your identity, and sending sketchy emails, going online can sometimes feel like a bigger hassle than it should. What’s more: some of the terms used to describe this shady behavior almost sound made up. Especially ones like bluesnarfing, which is actually a real thing. A relatively new kind of cyberattack is called cryptojacking, and while the name is silly, the attack is anything but.

What is cryptojacking? – Microsoft 365 (1)

What does “cryptojacking” mean?

Cryptojacking is when criminals illicitly use other people’s devices to mine for cryptocurrency. This can mean their phones, tablets, laptops, and even the servers at larger companies can be used to help cyberjackers generate a profit by mining for digital currency. In short, cryptojacking isn’t limited to individuals; it can affect institutions and industrial control centers too.

What is cryptojacking? – Microsoft 365 (2)

Microsoft Defender

Stay safer online with one easy-to-use app¹

¹Microsoft 365 Personal or Family subscription required; app available as separate download

Learn More

How does cryptojacking work?

The end goal of these hackers is to make money in the form of cryptocurrency. A victim will unwittingly install a program, run a script, or click a link that allows a criminal to access their computer or mobile device. From here, the cryptojacker will use this installed program to create, or mine, for cryptocurrency, and will hijack the victim’s computing power to do so.

Cryptocurrency functions via on a database called a blockchain, which is regularly updated with a list of transactions that have taken place. Each set of transactions is referred to as a block and is put together via a complex formula. For each new block to be produced, a large amount of computing power is needed, which is where the cryptojackers come in.

They install programs on others’ computers and hijack their computing power to help build the blockchain so that they can be rewarded with cryptocurrency. It takes a huge amount of power to mine for cryptocurrency and build up the blockchain, which can equal a rather hefty electric bill. Rather than pay these high electric bills, hackers will let their victims foot the bill for any incurred costs.

How could I get hacked by a cryptojacker?

When you read about hacking, there are usually a few main routes that criminals will take to access your device and your data. Cryptojackers are no different, and usually operate via one of two ways:

Getting a victim to click on a malicious link in an email that loads a code into a computer
Infecting a website or ad with a code that executes once it’s loaded into a browser

In both cases, the code will load a script that hijacks the device to mine for crypto in the background without being detected by the victim. Cryptojacking scripts don’t damage computers or steal data—they’re only after processing power. An individual may notice an annoying performance lag, but a business that’s been cryptojacked may incur hefty costs in electric bills and need IT help to track down and address the issue.

There have been several high-profile examples of this type of criminal activity. In 2018, criminals targeted critical infrastructure and impacted the systems of a water utility company in Europe, which affected its ability to provide services to citizens. Due to the enormous amount of stolen computing power, the cryptojacking event seriously impacted the utility’s ability to be managed.

How to detect and protect against cryptojacking

It can be hard to tell if you’ve been cryptojacked since the scripts are intentionally made to be hard to detect. But there are a few things to look out for, and a few ways to protect yourself:

One main clue that your computer is running a cryptojacking script is decreased performance. If your device seems to be draining battery at a rapid rate or crashing all the time without reason, you may be hacked.
If your device seems to be overheating more often, or you notice that your laptop’s fan is running faster than usual, you may have been targeted.

When it comes to protection against cyber-attacks, a comprehensive cybersecurity program is key. These programs are constantly updated to detect new threats and can provide protection against different types of malware.

Find peace of mind online with Microsoft Defender, an easy-to-use app can help streamline your online security, keeping you, your devices, and your information safe. View more privacy and safety tips to help you stay secure online.