Two warring families of malware have caused a failure in the work of the Californian operator of communication Sierra Tel. The problem arose on April 10 of this year, when the company's customers complained about the lack of an Internet connection. First, the cause of the failure was considered the installation of firmware updates for modems, however, according to the statement made by Sierra Tel, the company became a victim of a "malicious hacker incident".

As the operator of communication has informed, unknown malefactors have cracked modems Zyxel HN-51 and disconnected them from the Internet. As the number of attacked devices grew rapidly, the company asked its customers to turn off modems in their offices and began replacing them with others. Obviously, Sierra Tel underestimated the situation, as the modems for replacement quickly ended, and customers continued to line up for new devices.

The attention of Bleeping Computer journalists to the incident was attracted to someone under the pseudonym janit0r, allegedly being the author of the BrickerBot malware for IoT devices. According to a letter from him, when the Sierra Tel customers had problems with modems, BrickerBot was active on the company's network. At the same time, the devices were infected with other malware, and the simultaneous activity of the two programs could cause a disconnect from the Internet.

According to janit0r, the second malicious program is Mirai. However, it can be any of the numerous malware families for IOT devices such as Hajime, Wifatch, Gafgyt, Imeij and t.

As previously reported by janit0r, BrickerBot was designed to protect vulnerable devices of the "Internet of things". However, in case of failure, it erases the flash memory of the infected gadget and writes random data into it, thus making it unusable. Such devices need to be repaired or replaced, as happened in the case of Sierra Tel.