Many people probably remember that recently malware was found preinstalled on many Chinese Android gadgets. At that time this news did not cause much surprise, because it was to be expected from little-known companies. Now it appears that you will run into a smart phone with preinstalled viruses even when buying a device from a well-known vendor.This information was recently published by representatives of the Check Point company. Their research showed the presence of malware preinstalled on 38 Android gadgets. However, additional checks reduced that number to 36. Nevertheless, the list included devices from such well-known companies as Samsung, Lenovo, LG, Asus, Xiaomi, etc. Basically, the malware detected was littering devices with ubiquitous ads. Nevertheless, among them there were more serious ones, engaged in stealing users' personal data. One of the most troublesome of these was Slocker. First, it encrypts files on the device using the AES algorithm and then demands a certain amount of money for the key needed to decrypt them. However, the most dangerous of the detected viruses pre-installed on the tested gadgets was Loki. It consists of several components that work separately from each other. While some of them simply bring profit to the intruder by forcing the victim to view ads, others are engaged in installing the malware in the system to gain full control over it. Check Point specialists note that such viruses are not part of the official firmware and end up on devices together with software provided by someone from the vendor. It is also worth adding that some of the detected malware are installed using system privileges, which makes it impossible to remove it without "re-flashing" the device. This research has shown us all that even buying a gadget from a well-known and trusted company does not guarantee that it is free of preinstalled malware. Therefore, simple precautions when visiting dubious resources and installing new applications are often not enough. Sometimes, only timely installation of antivirus software, such as, for example, Kaspersky Antivirus & Security or ESET Mobile Security & Antivirus, can save you from possible problems.