ovirt-provider-ovn installed using engine-setup might have it's password stored unencrypted in the engine database. The problem occurs in some pre-4.2.1 engine-setup versions. To fix the problem in existing ovirt-provider-ovn isntances, it is enough to open the network provider dialog (Administration -> Providers), choose the appropriate network provider, open it by clicking "Edit", and confirm changes by clicking the "OK" button.