Miner viruses: What are they and how to remove miners from your PC

What Are Cryptomining Viruses?

Cryptomining viruses are a form of malware that covertly infiltrates computers, smartphones, or other digital devices. Their primary purpose is to exploit the infected device's processing power to mine cryptocurrency—generating digital coins for attackers.

This type of malware effectively turns your device into a "mining farm" that operates for cybercriminals. All profits from mining go to the perpetrators, not the device's owner. Victims experience only the downsides: slower device performance, overheating components, and higher energy consumption.

The core function of a cryptomining virus is to initiate a hidden mining process that constantly solves complex mathematical problems to generate new cryptocurrency blocks. The virus typically runs in the background, aiming to stay undetected as long as possible. Its activity puts heavy stress on the CPU and GPU, causing noticeable lag and overheating.

Prolonged operation under heavy load leads to accelerated hardware wear. Processors and graphics cards may fail prematurely, resulting in costly repairs or replacements. Electricity costs also rise significantly, as the device runs at peak power around the clock.

Who Develops Malicious Miners and Why?

Cybercriminals—usually organized hacker groups—develop and distribute cryptomining viruses to generate illicit profits. These attacks are known as cryptojacking (cryptojacking), referring to the unauthorized use of others' computing resources for cryptocurrency mining.

This type of cybercrime surged in popularity in the late 2010s, when cryptocurrencies—especially Bitcoin and other digital coins—experienced sharp price increases. Attackers saw an opportunity to profit by exploiting other people's computers instead of investing in costly hardware.

Cryptomining viruses are attractive to cybercriminals for several reasons. First, they operate stealthily, so victims may remain unaware for a long time. Infected devices may lag or overheat, but many users attribute this to aging hardware or software glitches.

Second, unlike ransomware or data-stealing Trojans, miners don't attract attention with dramatic disruptions. They don't block file access or steal personal data, reducing the chance of quick detection and removal.

Third, creating and distributing miners requires little technical expertise—readymade solutions and custom malware services are widely available on the darknet.

How Do Infections Occur?

Cryptomining viruses can infect devices in many ways. Understanding these attack vectors helps you better defend against them.

Main Infection Methods

Downloading infected software is among the most common methods. Miners disguise themselves as pirated programs, Windows activators, game cracks, or other sought-after applications. Users who download such files from torrents or unreliable websites install the virus alongside the desired software.

Via dropper viruses—small pieces of malware that first sneak onto a computer, then download and install the miner. Droppers may be embedded in various files or exploit system vulnerabilities.

Through email and phishing—attackers send emails with infected attachments or links to phishing sites. When users open the attachment or click the link, the miner is downloaded to their device.

Exploits and network worms—some miners spread automatically, exploiting vulnerabilities in operating systems or installed applications. They can independently locate and infect vulnerable devices on a network without user involvement.

Via browser scripts—in this scenario, mining happens directly in the browser when visiting certain sites. Malicious JavaScript code uses your computer's resources for mining while you're on the page. This method doesn't require software installation, but only works when the browser is open.

Can Smartphones Be Infected?

Yes, mobile devices are also vulnerable to cryptomining viruses. Mining malware exists for Android, and numerous incidents have been recorded where hidden miners were embedded in mobile apps—some even made it onto the official Google Play store.

Mobile miners are usually less efficient than desktop versions due to smartphones' limited processing power, but they still pose serious risks: rapid battery drain, overheating, and potential hardware failure. Overheating lithium-ion batteries can also be dangerous.

Examples of Major Malicious Miners

In recent years, cybersecurity professionals have identified many cryptomining viruses. Here are some of the most notorious and dangerous:

CoinMiner—a catch-all term for numerous mining Trojans targeting various cryptocurrencies. These viruses often spread via infected files and exploits.

XMRig—originally a legitimate mining tool for Monero. Due to its efficiency and open-source nature, XMRig is often weaponized by cybercriminals and deployed covertly on victims' systems for unauthorized mining.

WannaMine—a self-propagating miner that exploits Windows vulnerabilities to automatically infect other computers on a network. This virus poses a particular risk to corporate networks, where it can spread rapidly to many devices.

HiddenMiner—a mobile miner designed for Android devices. It embeds itself in popular apps and runs in the background, causing overheating and rapid battery depletion.

Smominru—one of the largest mining botnets ever discovered, infecting over 500,000 servers and computers worldwide. The scale of this botnet generated enormous profits for its operators.

How Much Can Criminals Earn from Miners?

Profits from distributing cryptomining viruses can be substantial. According to cybersecurity research:

By 2018, about 5% of all Monero in circulation had been mined illegally using cryptomining malware, totaling around $175 million. These numbers highlight the scale and appeal of this cybercrime.

In the second half of 2017 alone, cybercriminals made over $7 million from malicious miners—a period marked by intense activity driven by rising crypto prices.

Large botnets of thousands of infected devices can generate hundreds of thousands of dollars per month for operators. Startup and maintenance costs are relatively low, making this a highly lucrative form of cybercrime.

It's crucial to recognize that these profits come at the expense of infected device owners, who pay for increased electricity, hardware repairs, and lost productivity.

How to Detect Cryptomining Infections

Early detection minimizes damage to your device and helps prevent further malware spread.

Main Signs of Infection

Performance drops—your computer slows down even during basic tasks like web browsing or document editing. Programs take longer to open and the system becomes less responsive.

Device overheating—if your computer or laptop heats up even when not running demanding apps or games, this may indicate hidden mining. Fans may speed up and become noisier.

Suspicious programs running—Task Manager displays unfamiliar processes or processes consuming excessive CPU or GPU resources.

Constantly high CPU/GPU usage—even when idle and with no programs open, CPU or GPU utilization remains at 70–100%. This strongly suggests a background mining process.

System lag and freezing—programs open much slower than usual, video playback stutters, and the system may freeze intermittently.

Rapid battery drain—for mobile devices, a quickly draining battery is a classic warning sign. Your phone may heat up and lose charge much faster, even with minimal use.

Antivirus alerts—your antivirus may warn of threats like Trojan.Miner, Riskware.Miner, or similar, which directly indicates a mining infection.

Increased network traffic or suspicious network activity—miners often communicate with remote servers, resulting in higher network traffic and unfamiliar connections in your network settings.

How to Remove a Miner

If you notice signs of a cryptomining virus, act swiftly to halt malicious activity and prevent further damage.

How to Manually Remove a Miner from a PC

Manual removal requires some technical skill, but can be effective:

1. Disconnect from the internet—this prevents the miner from sending data or downloading additional malware.

2. Identify and end suspicious processes—open Task Manager (Ctrl+Shift+Esc), check the "Processes" tab, and look for those with high CPU or GPU usage or suspicious names.

3. Find the miner's file location—right-click the suspicious process and select "Open file location" to pinpoint the virus executable.

4. Delete virus files—after identifying the location, delete the miner file and any related files in the same folder.

5. Clear startup and scheduled tasks—review your startup items (via msconfig or Task Manager) and Windows Task Scheduler. Remove suspicious entries that could relaunch the miner at startup.

6. Restart your PC—always reboot after removing files.

7. Scan the system with antivirus software—perform a full system scan to detect any remaining malware.

How to Remove a Cryptomining Virus with Free Tools

Specialized antivirus tools are often safer and more reliable:

Dr.Web CureIt!—download this free tool from Dr.Web's official site and run a complete system scan. Once threats are detected, click "Neutralize" to automatically remove them.

Microsoft Defender—the built-in antivirus for Windows, available on all modern versions. Open Windows Security Center, go to "Virus & threat protection," and select a full system scan.

Other free antivirus solutions—options include Malwarebytes Free (excellent for malware detection), Kaspersky Virus Removal Tool (a powerful scanner), ESET Online Scanner (no installation needed), and Zemana AntiMalware Free (effective against stealth threats).

What If the Miner Can't Be Removed?

Some cryptomining viruses use self-protection mechanisms that make removal difficult:

• Scan in Safe Mode—reboot your PC into Safe Mode (usually by pressing F8 at startup) and run antivirus scans. Many malware defenses are disabled in Safe Mode.

• Try another utility—if one tool fails, use different antivirus solutions; they use varying detection methods.

• Check and remove autoruns and registry tasks—some miners bury themselves deep in the registry. Use Microsoft's Autoruns utility to find all auto-starting elements.

• Consult support forums—specialized antivirus support forums have experts who can help with stubborn threats.

• As a last resort—reinstall the OS—if all else fails, a complete operating system reinstall with disk formatting will remove any virus. Be sure to back up essential data first.

How to Protect Your Computer from Hidden Miners

Prevention is far easier and less costly than fixing an infection. Follow these tips to defend your device:

Install reputable antivirus software and keep it active—up-to-date antivirus software can detect and block most known miners early. Never disable protection, even temporarily.

Keep your OS and software updated—install all security updates for Windows and your applications. Many viruses exploit vulnerabilities that updates have already fixed.

Avoid downloading software from untrusted sources—only use official developer sites. Avoid torrents, file-sharing platforms, and shady sites offering "free" versions of paid software.

Use caution with email and links—don't open attachments from unknown senders. Verify links before clicking, and be especially wary of messages urging immediate action or making enticing offers.

Use ad and script blockers in your browser—install extensions such as uBlock Origin or NoScript to block hazardous scripts and ads, protecting against browser-based miners and other online threats.

Monitor device health—regularly check Task Manager for suspicious processes and high resource usage. Watch for behavioral changes such as slowdowns, overheating, or louder fans.

Back up important data—regular backups ensure you can restore your data if a severe infection requires a system reinstall.

Use a limited user account—perform daily tasks using a non-administrative account to restrict malware's ability to alter system settings.

FAQ

What are cryptomining viruses (Cryptominer) and how do they work?

Cryptomining viruses are malware that harnesses your device's processing power to mine cryptocurrency without your permission. They are secretly downloaded and run, consuming electricity and slowing system performance.

How can I tell if my computer is infected with a cryptomining virus? What are the symptoms?

Common signs include: your graphics card overheating with loud fan noise, sharp system slowdowns, high memory and CPU usage, unfamiliar processes in Task Manager, and higher electricity bills.

What harm do cryptomining viruses cause to computer systems?

Cryptomining viruses degrade system performance, cause overheating, and speed up hardware wear. They consume substantial CPU and GPU resources in the background, reducing system efficiency and component lifespan.

How can I fully remove and clean a cryptomining virus from my computer?

Terminate suspicious processes in Task Manager, disable suspicious services, use specialized malware removal tools (Malwarebytes, AdwCleaner), run a full antivirus scan, and reinstall the OS if necessary.

Which antivirus programs can detect and remove cryptomining malware?

Kaspersky, Bitdefender Free, and Avast/AVG Free are effective at detecting and removing cryptomining malware. These tools offer powerful detection capabilities and regularly updated databases for robust protection.

How can I prevent cryptomining virus infections? What are the best preventive measures?

Use an up-to-date antivirus and firewall, regularly update your OS and applications, avoid downloads from unreliable sites, and don't open suspicious emails or links. Monitor CPU and GPU usage, install browser script-blocking extensions, and check system processes regularly.

Cryptomining viruses vs. ransomware: what's the difference?

Cryptomining viruses use your PC's resources to mine cryptocurrency, lowering system performance. Ransomware encrypts your data and demands payment for its release. Miners steal computing power; ransomware blocks access to your information.

How much can computer performance drop after a cryptomining infection?

Performance may drop by 30–70% due to the miner's heavy CPU and memory usage. Prolonged infections also cause hard drive wear and file system degradation, further slowing the system.