Hidden enemies of your PC: How to identify cryptojacking and protect your system

The popularity of cryptocurrencies has led to the rise not only of legitimate mining but also of its shadow side — malicious software that ruthlessly steals your machine’s computing resources. Such programs operate in complete stealth, enriching criminals at the expense of slowing down your device and increasing electricity bills. Have you ever wondered why your PC suddenly started running slower or the fan began roaring like an aircraft engine? This could be a sign that an uninvited guest has taken up residence in your system. In this article, we will explore what such a threat is, what signals indicate its presence, and how to detect a miner on a PC step-by-step.

Understanding the essence of the problem

When it comes to malicious cryptocurrency mining software, it is important to clearly distinguish two concepts. Mining itself is a legitimate process where the user consciously runs a program to obtain crypto assets. It’s a completely different matter when an attacker installs a program on your computer without your consent.

What happens in this case? Malicious software hijacks the power of your CPU and GPU, using them to solve complex mathematical problems. The results are sent to the criminals’ servers, who receive cryptocurrencies like Monero, Bitcoin, or Ethereum( at the expense of your electricity and hardware wear and tear. This process is called cryptojacking, and this phenomenon is becoming increasingly common.

Recognizing the enemy: main symptoms of infection

Before figuring out how to detect a miner on a PC, you need to learn to notice signs of its presence. The system usually shows the following signals:

Performance slowdown — the computer begins to lag even when performing simple operations. Opening files, loading browsers, switching between programs — everything is slower than usual.

Maximum CPU load — even when you’re not doing anything, CPU or GPU usage indicators stay at 70-100%. This is clearly abnormal for idle mode.

Thermal issues — your laptop or desktop starts heating up unnaturally. Fans run at full capacity, making loud noise, and the device feels hot to the touch.

Increased electricity bills — energy consumption suddenly spikes without visible reason.

Strange processes in the system — when opening Task Manager, you see unknown programs consuming significant resources and having suspicious names.

Browser changes — new extensions appear unexpectedly, pages load slower, or tabs with unfamiliar resources open automatically.

If you notice even a few of these signs, it’s time to conduct a detailed system check.

Method 1: Diagnostics via Task Manager

Let’s start with the simplest and most accessible method. How to detect a miner on a PC using built-in operating system tools?

For Windows:

1. Press Ctrl + Shift + Esc simultaneously — the Task Manager window opens
2. Go to the “Processes” tab
3. Sort the “CPU” column in descending order to see which programs are “eating” the most resources
4. Look for processes with suspicious names: sysupdate.exe, miner.exe, rundll64, cryptominer, and similar
5. If you find something strange, right-click and select “Open file location” — this will help you understand where the program is located

For macOS:

1. Open “Activity Monitor” )via Spotlight or Applications → Utilities(
2. Go to the “CPU” tab
3. Sort by CPU usage in descending order
4. Check unknown processes and their system load

Remember: legitimate system processes usually have clear names and belong to Microsoft or Apple. If something looks strange or has a blurred version or publisher, it’s a cause for concern.

Method 2: Antivirus scanning — reliable protection

Task Manager provides only superficial information. For a thorough search, you need to use specialized software.

Which antiviruses most effectively handle cryptojacking:

Kaspersky — one of the best at detecting mining trojans thanks to a constantly updated malware database. It effectively detects both known and new variants.

Malwarebytes — specializes specifically in hidden threats and often finds what other antiviruses miss.

Bitdefender — a lightweight and fast option that doesn’t freeze the system during scans.

Scanning process:

1. Download the chosen antivirus from the official website
2. Install and update the virus signature database )this is important!(
3. Run a full system scan )this will take some time, allocate several hours(
4. After completion, check the quarantine — where detected threats are stored
5. Remove all found items and restart

Method 3: Checking autorun

Many cryptojacking programs are programmed to start automatically when the computer is turned on. This allows them to remain in the system even after reboot.

How to check on Windows:

1. Press Win + R and type “msconfig”
2. The System Configuration window opens
3. Go to the “Startup” tab
4. Carefully review the list of programs launching at startup
5. Disable all unfamiliar or suspicious items )uncheck(
6. Click Apply and OK, then restart

For macOS:

1. Open “System Preferences”
2. Go to “General” → “Login Items”
3. Review the list of programs that load at startup
4. Select suspicious items and remove them by clicking the “-” button

This procedure often helps eliminate the malware from relaunching after removal.

Method 4: Browser analysis and extensions check

Web mining is one of the popular ways to spread cryptojacking. Infected sites or malicious extensions can use your browser’s power to mine cryptocurrencies.

What to check:

In Chrome:

• Open “Settings” → “Extensions”
• Review all installed plugins
• Remove anything you don’t remember installing or that looks suspicious
• Malicious extensions often have strange icons or blurry descriptions

In Firefox:

• Open menu → “Add-ons”
• Check extensions and themes
• Disable or remove unknown items

Additional actions:

• Clear browser cache and cookies )this will remove residual malware data(
• Install blocker extensions like MinerBlock or Adblock Plus
• Disable JavaScript on suspicious sites )this prevents web mining(

Method 5: Using specialized tools

For experienced users, there are more advanced ways to detect threats.

Process Explorer )Windows( — provides detailed information about each process:

1. Download the utility from Microsoft’s website
2. Run it and look for processes with high load
3. Right-click on a process → online check to see if this process is known
4. Check the process path — it helps localize malware

Resource Monitor — built-in Windows tool for real-time monitoring:

1. Find it via search in the Start menu
2. Switch to the “CPU” and “Memory” tabs
3. Watch for background processes with high resource consumption
4. If a process constantly consumes resources without apparent reason — it’s a red flag

Wireshark — for network traffic analysis:

1. Install and open the program
2. Start capturing traffic on your network interface
3. Look for connections to unknown IP addresses or servers )miners often send data to crypto pool servers(
4. If suspicious connections are found, block them via firewall

Method 6: Network activity and connection analysis

Malicious mining software constantly sends data to remote servers. This can be tracked.

Via Command Prompt:

1. Open “Run” )Win + R( and type “cmd”
2. Enter “netstat -ano”
3. You will see a list of all active connections with server addresses and process IDs )PID(
4. Look at the addresses — if you see connections to strange IPs or crypto pool servers, it’s a sign of infection
5. Take the process PID and compare it with processes in Task Manager

Monitoring hardware temperature

Another indirect way to detect miner activity is to monitor thermal state.

Use programs like HWMonitor or MSI Afterburner:

1. Install monitoring software
2. Leave the computer idle )don’t open anything(
3. Check CPU and GPU temperatures
4. If temperatures are significantly higher than usual )for idle, typically 35-45°C for CPU(, it indicates intensive processing

Abnormally high temperatures during low load are classic symptoms of hidden miners.

Where do these threats come from?

Understanding infection pathways helps you be more cautious in the future:

Downloading from dubious sources — pirated software, cracks, activators, game mods, and torrents often contain mining viruses

Phishing emails — malicious links in spam emails or messengers can lead to infected sites

System vulnerabilities — outdated OS or browsers with known security holes are open gates for criminals

Visiting compromised websites — even legitimate sites can be hacked and start infecting visitors

Removing the enemy from the system

If you have definitively identified malware on your computer, here’s the action plan:

Immediate measures:

1. Open Task Manager and end all suspicious processes
2. Quarantine or delete threats found by antivirus
3. Reboot into Safe Mode with network support )for Windows, press F8 during startup(

Deep cleaning:

1. Use CCleaner to remove residual registry files
2. Run a full system scan again with antivirus
3. Check autorun items for leftovers
4. Scan the browser for remaining extensions

Extreme measure: If the miner has deeply embedded itself and cannot be removed by standard methods, reinstalling the OS is the only guaranteed way to eliminate the infection. This radical step ensures your system is clean.

Prevention — the best way to avoid problems

Preventing infection is much easier than dealing with consequences:

• Install reliable antivirus software and keep it updated )don’t rely solely on built-in Defender(
• Never download programs from torrents or dubious sites — use only official sources
• Use a VPN for additional protection when visiting unknown resources
• Regularly update your OS and browser — this patches vulnerabilities
• Be cautious with emails — don’t open links or attachments from unknown senders
• Disable JavaScript on suspicious websites
• Install browser extensions to block web miners

Final recommendations

Cryptojacking is a serious threat that can silently damage your equipment and wallet. Now you know how to detect a miner on a PC using built-in system tools, antivirus programs, and specialized utilities. Don’t ignore signs of slow performance or abnormal resource load.

By applying the diagnostic methods described in this material, you can detect the problem in time and neutralize the threat. Remember, being careful when choosing download sources, using up-to-date antivirus, and regularly updating your system are your best defenses against such malware. Take care of your system’s health and stay safe in the digital world.