Q1 2021 saw the appearance of two new botnets. News broke in January of the FreakOut malware, which attacks Linux devices. Cybercriminals exploited several critical vulnerabilities in programs installed on victim devices, including the newly discovered CVE-2021-3007. Botnet operators use infected devices to carry out DDoS attacks or mine cryptocurrency.
Another active bot focused on Android devices with the ADB (Android Debug Bridge) debug interface. The botnet was dubbed Matryosh (from the Russian word matryoshka — nesting doll) due to the multi-step process for obtaining the C&C address. It is not the first bot to attack mobile devices through a debug interface. This loophole was previously exploited by ADB.Miner, Ares, IPStorm, Fbot, Trinity, and other malware.