Description

RapperBot is a rapidly evolving botnet that first appeared in 2021 and has resurged in 2025, infecting over 50,000 IoT devices globally. The main target was initially on attempting DDoS attacks, RapperBot has now acquired extortion tactics, demanding $5,000 Monero (XMR) to stop further attacks. Unusually, it includes taunts and even rap lyrics hidden in its code, mocking reverse engineers and promoting the rapper "2tallforfood." Its victims span various sectors, including public services, social networks like Twitter, and AI platforms like DeepSeek. The infection process typically begins with scanning the internet for vulnerable IoT devices, exploiting weak Telnet passwords or known firmware vulnerabilities in DVRs, routers, and surveillance cameras. After compromising, device connects to botnet’s hidden C2 servers, identified through DNS-TXT records using which the RapperBot installs itself. The TXT records are encrypted and customized decoding algorithms are required and extract active C2 IP addresses making it difficult to trace. The connected devices are then registered with the botnet via specially crafted login packets sent, containing network details and random filler to bypass detection. RapperBot’s attack commands include starting or stopping DDoS floods, enabling proxy functions, and maintaining communication with the C2 through heartbeat messages. Communication is obfuscated using simple XOR encryption with random data to avoid signature-based detection. Each variant shows minor updates, such as different decryption keys, message sizes, or protocol tweaks, indicating active development and testing by its creators. The botnet also modifies its messages with each version, resembling a malware “mixtape.” RapperBot’s evolving growth highlights the need for better IoT security. Users should modify default passwords, regular updates of firmware, and limit public access to device interfaces. Network monitoring systems and threat intelligence should be used to detect unusual traffic patterns and block communication with known C2 domains.