According to new research published by Akamai on Tuesday, the technique is being harnessed by operators of a long-running cryptocurrency mining botnet campaign, in which BTC blockchain transactions are being exploited to hide backup command-and-control (C2) server addresses. Botnets rely on C2 servers to receive commands from cyberattackers. Law enforcement and security teams are constantly finding and taking down these C2 servers in order to render campaigns defunct -- but if backups are in play, takedowns can be more difficult. Akamai says that botnet operators are able to hide backup C2 IP addresses via the blockchain, and this is described as a "simple, yet effective, way to defeat takedown attempts."