Stories from a Customized Honeypot for the IoT

Since the inception of the Internet of Things (IoT), the security measures implemented on its devices have been too weak to ensure the appropriate protection of the data that they handle. Appealed by this, cybercriminals continuously seek out for vulnerable units to control, leading to attacks spreading through networks and infecting a high number of devices. On top of that, while the IoT has evolved to provide a higher degree of security, the techniques used by attackers have done so as well, which has led to the need of continuously studying the way in which these attacks are performed to gather significant knowledge for the development of the pertinent security measures. In view of this, we analyze the state of IoT attacks by developing a high-interaction honeypot for SSH and Telnet services that simulates a custom device with the ARM architecture. This study is carried out in two steps. Firstly, we analyze and classify the interaction between the attacker and the devices by clustering the commands that they sent in the compromised Telnet and SSH sessions. Secondly, we study the malware samples that are downloaded and executed in each session and classify them based on the sequence of system calls that they execute at runtime. In addition, apart from studying the active data generated by the attacker, we extract the information that is left behind after a connection with the honeypot by inspecting the metadata associated with it. In total, more than 1,578 malicious samples were collected after 9,926 unique IP addresses interacted with the system, with the most downloaded malware family being Hajime, with 70.5% of samples belonging to it, and also detecting others such as Mirai, Gafgyt, Dofloo and Xorddos.