You may not be aware of using these controllers but it’s time to check, and then check the patch status…:
Attackers are actively trying to exploit a critical, previously disclosed command injection flaw in a door access-controller system from Nortek Security and Control LLC to use the device to launch distributed denial-of-service attacks (DDoS).
SonicWall, which reported on the threat Saturday, said its researchers have observed attackers scanning the entire IPv4 address range space for the vulnerable systems in recent days. According to the security vendor, its firewalls have been blocking literally tens of thousands of hits daily from some 100 IP addresses around the world that are doing the scanning.
The command injection vulnerability [CVE-2019-7256] exists in products from Nortek’s Linear eMerge E3 Series access-controller family running older versions of a particular firmware. The access controllers allow organizations to specify the doors that personnel and others can use to enter and exit designated areas within a building or facility, based on their access rights.
Organizations in multiple industries currently use Nortek’s access controllers, including commercial, industrial, banking, medical, and the retail sector.
The injection flaw was among several vulnerabilities in Nortek’s Linear eMerge E3 Series family that industrial cybersecurity firm Applied Risk disclosed in May 2019. The company at the time described the flaw as allowing attackers to execute commands of their choice directly on the operating system.
The flaw has a CVSS score of 10, which is the maximum possible severity rating for any vulnerability. The issue is considered especially dangerous because it allows an unauthenticated attacker to gain complete remote control of the system.