Mirai and the IoT DDoS Attacks - A new Threat in Old Form

November 18, 2016

Mirai is a bot-net management framework targeting Linux-based IoT (Internet-of-Things) devices such as DVRs, CCTV systems, and IP cameras. It was the tool responsible for 2 of the largest DDoS attacks on record. And both of them happened in the past 2 months:

-In late September, the on hosting company OVH was attacked by 145607 cameras/dvr (1-30Mbps per IP). The attack traffic has exceeded 1.5Tbps.

-In Oct 21, one of the major DNS service providers Dyn, has suffered a massive DDoS attack from over 380,000 infected devices. Many prominent websites such as Amazon, Twitter and Spotify have experienced service outage for nearly 2 hours.

Mirai, the creation tool of the botnets, does not exploit any advanced vulnerabilities. It used only the oldest, simplist way of attack: the weak telnet password.

Mirai has hard-coded a dictionary of 63 username/passwords, most of them are default credential for popular IoT devices.[1]

The Mirai has become an open-source tool on github now, with more than 1800 folks. The password dictionary is located in mirai/bot/scan.c. Anyone could further develop it and create similar kind of DDoS attacks.[2]

In response of this incident, Xiongmai, one of the Webcam manufacture company, has recalled some of its products (mostly webcams), while strengthening password functions.

SonicWALL Gateway AntiVirus provides protection against this threat via the following signatures:

  • IPS 11999: Mirai Telnet Scanning


[1] https://krebsonsecurity.com/2016/10/who-makes-the-iot-things-under-attack/
[2] https://github.com/jgamblin/Mirai-Source-Code/tree/master/mirai
[3] https://www.hackread.com/mirai-botnet-linked-to-dyn-dns-ddos-attacks/
[4] http://dyn.com/blog/dyn-statement-on-10212016-ddos-attack/