goform/formEMR30 in Sumavision Enhanced Multimedia Router (EMR) 3.0.4.27 allows creation of arbitrary users with elevated privileges (administrator) on a device, as demonstrated by a setString=new_user<*1*>administrator<*1*>123456 request.
https://www.youtube.com/watch?v=Ufcj4D9eA5o
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-10181