From a recent report by Flashpoint
Manufacturer of Upstream Devices Identified
While investigating the recent large-scale DDoS attacks against targets including Krebs On Security and OVH, Flashpoint identified the primary manufacturer of the devices that utilize the default username and password combination known as root and xc3511, respectively. These types of credentials exist all across the Internet and are commonly used via Telnet to access numerous types of DVRs. In fact, countless DVR manufacturers buy parts preloaded with Linux and rudimentary management software from a company called XiongMai Technologies, located in Hangzhou, China. This company sells white-labeled DVR, NVR and IP Camera boards and software to downstream vendors who then use it in their own products. Altogether, over five-hundred thousand devices on public IPs around the world appear susceptible to this vulnerability.
... In fact, the majority of media coverage surrounding Mirai has outed Dahua products as a primary source of compromised devices. However, Flashpoint’s analysis on the attack data shows that while Dahua devices are indeed being compromised, a very large percentage of these IP involved in the DDoS attacks were hosting XiongMai Technologies-based products. The Dahua devices were identified early because of their distinctive interface and recent use in other botnets.