Nortek Linear eMerge E3-Series devices before 0.32-08f allow an unauthenticated attacker to inject OS commands via ReaderNo. NOTE: this issue exists because of an incomplete fix for CVE-2019-7256.
https://gist.github.com/omarhashem123/5f0c6f1394099b555740fdc5c7651ee2
https://eg.linkedin.com/in/omar-1-hashem
http://packetstormsecurity.com/files/167991/Nortek-Linear-eMerge-E3-Series-Command-Injection.html