An attacker can log into the local Niagara platform (Niagara AX Framework Versions 3.8 and prior or Niagara 4 Framework Versions 4.4 and prior) using a disabled account name and a blank password, granting the attacker administrator access to the Niagara system.
https://ics-cert.us-cert.gov/advisories/ICSA-19-022-01