The ovirt-engine-provisiondb utility, which is called by engine-backup if invoked with one of the options --provision*db, logs the username and password of the db user without redaction.
Name: Yedidyah Bar David (Red Hat)
This issue has been addressed in the following products:
Red Hat Virtualization Engine 4.2
Via RHSA-2018:2071 https://access.redhat.com/errata/RHSA-2018:2071