Coin Miners – What is it? How to know that you are infected?

Throughout the timeline of trojan virus evolution, it obtained a lot of different forms. Nowadays, they become a global malware that can exploit your computer as it wants. In this article, I will tell you about the peculiar type of trojan virus – trojan-miner, also known as coin miner¹.

Coin miners: essence, spreading and reasons for appearing

First trojan viruses that had the ability to use the infected machine for cryptocurrency mining appeared in 2016. But their appearance was not explosive: there was no reason for their massive distribution. Cryptocurrencies were still unpopular, their prices were low, so the cyber burglars saw no potential in such a type of malware.

The things changed in 2017, when the first cryptocurrency rush occurred². Bitcoin reached the $20000 price tag for single coin, and other crypto coins, like Ethereum, Litecoin or Ripple, were also on their highs. This type of equity has attracted (and still attracts) the big money, and where the big money is, the people who want to have an illegal bite of this money appear.

Peak of trojan-miner activity was reached in March 2018. When the price of Bitcoin shed back to $5000, coin miners activity dropped, too. The strict correlation between miners activity and cryptocurrencies price can easily be proofed by the graphic below.

In summer, 2020, when the cryptocurrencies price began pumping, again, trojan miners quickly rose to the peak of 2018, and kept going as the Bitcoin price rose to $40000. Nowadays, coin mining trojans are as active as they have never been before.

How can I detect that my PC is infected with coin miner trojan?

Have you ever tried to use the old computer with a new OS? The system freezes on every operation because of the lack of RAM memory and slow reading speed of HDD, so the operating system is forced to load the files from RAM out to the swap file. Coin miners can force you to remember these feelings. Your CPU and GPU are loaded to 100%, regardless or the amount of launched programs. Google Chrome opens more than one minute, the attempt to open Photoshop may lead to its crash, and you can do nothing to deal with this problem. And it doesn’t matter if your computer is a high-end machine or not – even systems with Core i9-10900/Ryzen 7 3700X and RTX 3090 will suffer.

If you have the described symptoms, you definitely have the coin miner in your system. The last thing that can ensure this decision is a strange process in the Task Manager. Sometimes, coin miner developers do not try to hide it, naming the process created as “cminer” or “trjminer”. Whatever it was, this process will consume an enormous amount of your CPU/GPU capacities, so you will easily distinguish it among other processes.

Are coin miners dangerous?

There is a widespread misconception that coin miners carry no danger for your computer, because they just load your hardware to the max values. Such a conception may be true for the users who check their PC regularly, to detect any hardware issues, such as dust in the coolers, or some breaking in the moving parts. But what about the average users, who clean the dust from the cooling fan only after it starts to whine loudly after the PC launch? Or individuals who have a bad/weak power supply, so it generates the pulsating current?³

In the mentioned cases, a long overload with a high chance may lead to the components breaking. The CPU is sensitive to overheating, and it is quite a simple task to make it boiling hot with a malfunctioning cooling system. Pulsating current is even more dangerous: such a voltage volatility can easily break some of the components, as well as kill the whole motherboard, so you will need to buy a new one besides the broken hardware.

And the danger of hardware damage is not the single thing you need to be afraid of. Due to the modern trend of making the virus complex, your PC will likely be infected with numerous other viruses. Spyware, keyloggers, adware, backdoors, and even ransomware – choose what you like. The possible danger that may be carried by these malware is enormous – data/credentials stealing, file encryption, including your PC to the botnet, remote controlling – that is not a full list of the consequences. It is recommended to scan your computer as soon as possible and remove all malicious items you have in your system. The special guide for trojan-miner removal is posted as a separate article – read it to get a relevant and efficient guide.

1. Detailed investigation of the coin mining trojans.
2. Cryptocurrency rush description on Wikipedia.
3. About the dangers of bad power supply usage.