Cryptojacking Definition + 12 Tips on How to Detect & Prevent It

In the thriving digital landscape of cryptocurrencies, there are almost as many threats as there are opportunities. One such hazard—called cryptojacking—is as subtle as it can be malicious.

While the term itself sounds as if it’s coming from a cyberpunk novel, the threat itself is very real, and it’s affected countless individuals and corporations. Moreover, chances are that some of the targets of cryptojacking have no idea they’ve been taken advantage of!

You don’t even have to be a crypto enthusiast to benefit from this article, as it concerns anyone who uses their PC or smartphone to go on the internet. Keep reading to find out exactly what cryptojacking is and how you can protect yourself from it.

What Is Cryptojacking?

Cryptojacking is a malicious activity where bad actors—either individuals or organizations—use the hardware of unaware individuals to mine cryptocurrency (mostly Bitcoin and Monero).

Hackers can take advantage of almost any device that’s capable of connecting to the internet, including personal computers, tablets, smartphones, and server machines by:

• Embedding malicious scripts on websites that users visit
• Injecting cryptojacking malware directly onto someone else’s hardware

The main motivation behind cryptojacking is profit. Although cryptocurrency mining can be a highly lucrative endeavor, the high costs of the necessary equipment and electricity typically reduce its benefits. As a result, cryptojackers ‘steal’ other people’s device’s computing power and energy to get mining rewards for themselves.

On the other end, the victims might not even notice that they’ve been targets of these attacks, as cryptojacking generally doesn’t damage data or operating systems. However, it can lead to an increase in electricity bills, a slowdown in device operation, and permanent damage to the victim’s hardware.

How Does Cryptojacking Work?

Cryptojacking works by using the victim’s computing resources to solve complex mathematical problems and mine cryptocurrency like Bitcoin and Monero. One of its biggest dangers is that it happens subtly and often without the victim’s knowledge.

Here’s how the cryptojacking process works in general:

• Infection vector. The attacker first needs a way to deploy a mining script on another user’s device. Some scripts start running when users visit infected websites. Other scripts are designed to run through online ads or along with other software.
• The mining process. When a user visits an infected website or runs an infected application, the crypto mining process starts in the background. In many cases, the mining continues even after closing the website or the app. These scripts can be hard to detect since they can run as pop-unders or disguised system processes.
• Mining pools. Hackers often infect many devices simultaneously to connect them to a mining pool and increase mining efficiency. Mining rewards are proportionate to the hashing power of the hardware used to solve cryptographic puzzles. As a result, hackers always aim to infect as many devices for as long as possible.
• Secrecy and persistence. Cryptojacking gets more profitable the longer hackers can remain undetected. One way to achieve that is to modify script code to only use a fraction of the computing power of each device. That way, it becomes much harder for an individual to discover them.

Cryptojacking, by definition, refers to a malicious process. However, some website owners used to ask visitors for permission to use their hardware for mining.

In essence, visitors would agree to “lend” the processing power of their device in exchange for enjoying the content of those sites for free. Still, there was concern about whether the claims on these sites were honest.

Examples of Cryptojacking

Cryptojack attacks don’t only happen to individuals. Let’s check out two examples of cryptojacking on a large scale.

#1. European Water Utility System

In 2018, a security firm called Radiflow discovered cryptojacking malware in the network of a European water utility's industrial control system. The research found malware to be designed to use as little processing power as necessary to mine Monero. This allowed it to stay undetected for an undefined amount of time.

On top of that, the malware could detect and disable systems that would otherwise discover it. Research indicates that the attack wasn’t targeted and that hackers were only looking to exploit unused processing power. Regardless, it raised concerns regarding how much more damaging a serious attack could be.

#2. Microsoft Store Apps

In 2019, a cybersecurity firm called Symantec discovered stealth mining code in several apps in the official Microsoft app store. The cryptojacking code was a part of these applications, and it was designed to mine Monero (which is known to be confidential and untraceable) without the user’s consent or knowledge.

Some of these applications were among the top free apps in the store and reportedly included web browsers, video editing apps, optimization software, and more. They were published by three different companies in a period between April and December of 2018. However, the research suggests the publishers were likely the same entity.

How to Recognize Cryptojacking

Learning how to detect cryptojacking is one of the best ways to prevent or stop it. Let’s examine how you can identify if you’ve been targeted by a cryptojack attack.

#1. Device Overheating

One of the biggest signs of cryptojacking is when your device suddenly starts overheating. If a mining script is designed to use all the available computing power of a victim’s device, it’ll force it to work at full capacity all the time.

When a device works under full load, it draws a lot of electricity, which causes it to overheat. While this symptom isn’t definite proof of cryptojacking, it’s vital to work out why it happens. Needless to say, prolonged device overheating can lead to permanent hardware damage.

#2. Unexpected Electric Bill Increase

A device used for crypto mining consumes more electricity, which can result in unexpected increases in electric bills. If you notice a sudden spike in your electricity bill without a change in typical usage, that might be an indicator of a cryptojack attack.

Oftentimes, cryptojacking scripts will be set up to use just a fraction of a device’s computing power. That means they won’t cause overheating, which makes them harder to discover. Still, even several percentage points of increase add up on a monthly basis, resulting in higher bills.

#3. Decreased Device Performance

Another strong indicator of a mining script is a drop in performance for no apparent reason. If your personal computer, tablet, or smartphone suddenly starts working slower than before, it could be mining cryptocurrency without your knowledge.

Cryptocurrency mining generally uses CPUs or GPUs to perform complex calculations and solve cryptographic puzzles. If you notice lag while using resource-heavy software and applications or even during everyday use, it might be due to a cryptojacking script.

#4. Unknown Processes or Applications

If you spot unfamiliar processes or applications running on your device, they might be associated with cryptojacking. Some of the ways to check what processes are currently running on your device are via the Activity Monitor on macOS or the Task Manager on Windows.

#5. Unusual Network Activity

Unexpected network traffic is another strong sign of cryptojacking. Since devices mining cryptocurrency often need to receive instructions and send crypto, you might notice a spike in data usage, transfers, or outgoing connections.

How to Protect Yourself From Cryptojacking

The best way to protect yourself from cryptojacking is to prevent hackers from ever accessing your device. Let’s see some of the best methods for doing that.

#1. Monitor Continuously

You should continuously monitor your device’s performance and CPU usage. If you notice any unexpected power spikes, unauthorized processes, or performance issues, you should immediately start working on finding the root cause. That’ll mean that you’re already being attacked, but at least you can promptly act and solve the issue.

#2. Use Browser Extensions

There are several browser extensions that prevent cryptojacking website scripts from running when you visit these sites. Notable examples include No Coin and CryptoMining Blocker. Some browsers (e.g., Firefox) have built-in cryptojacking protection features that you can access in the settings.

#3. Use Antivirus Software

Modern antivirus and antimalware software can detect and block cryptojacking scripts. Make sure to do your research and use software from a reputable company. Furthermore, you should ensure that it’s always active and updated.

#4. Disable JavaScript

Most of the cryptojacking scripts on websites run on JavaScript. As a result, disabling JavaScript in your browser or on specific websites where it’s not necessary will vastly improve your protection against bad actors.

However, keep in mind that there may be other website features that require JavaScript. By disabling it, you could also disable some functionalities that would be handy or even necessary for the site to operate properly.

#5. Be Wary of Phishing Attempts

One of the many dangers of phishing emails is that they can inject cryptojacking malware into your device. That’s why you should always follow the best practices when it comes to internet security. Avoid clicking on any suspicious links or opening questionable attachments. Furthermore, you should always check and verify the sender’s information.

#6. Update Your Software

You should regularly update all software that you’re using. Everything from an outdated operating system to drivers and antivirus software could make your device vulnerable to attacks.

Hackers are continuously improving their scripts to bypass security measures. On the other end, when software developers find potential weaknesses or new threats, they patch them up with security updates. Having the latest updates leaves you least susceptible to attacks.

#7. Practice Continuous Learning

Being educated on cryptojacking practices is one of the best ways to protect yourself. Hackers don’t just constantly work on improving their scripts; they are always looking for new ways to penetrate your devices without your knowledge.

Due to this, it’s crucial to be aware of all the different methods that malicious actors can use to take advantage of your hardware’s computing power and turn it into their mining rig.

How to Respond to Cryptojacking

Finding out that you’re the target of a cryptojacking attack can be alarming and requires a swift response. However, it can be comforting to know that the majority of these scripts don’t damage your data or system beyond exploiting hardware to mine Bitcoin and other cryptocurrencies.

Regardless, here are a few tips to help you best respond to these incidents:

• Isolate the affected device. By disconnecting from the network and cutting communication with the script’s server, you can stop it from working until you find a way to remove it. Moreover, some cryptojacking malware acts as computer worms, which means it can affect every other device on the same network.
• Scan your system. Install reputable antivirus or antimalware software and use it to run a system-wide scan. Chances are it will detect and quarantine or delete the mining script and any related malware.
• Update all software. Software updates often contain security patches that remove known vulnerabilities. You should particularly pay attention to your operating system, antivirus, and other security software, browsers, and plugins.
• Consider a system reinstall. While this is the most extreme solution compared to the other ones listed, it has the highest chance of solving any problems. As long as you don’t have any important data on your device, a clean system reinstall will most likely remove any malicious software, including cryptojacking scripts.

Key Takeaways

The bottom line is that cryptojacking is the theft of the victim’s electricity and their hardware’s computing power. It can often pass undetected for extended periods of time and might not do more damage than incurring a slightly larger electricity bill.

On the other hand, it can be highly dangerous. Some mining scripts cause excessive overheating and permanent hardware damage. Moreover, they can be bundled up with other malware, causing even more trouble.

That’s why it’s crucial to know about the process, follow the best security practices, and stay updated on the latest hacking methods. Stay safe!