After upgrading OpenShift cluster to version 3.9, we've started experiencing a problem with Vault-controller pod which keeps crashing with an error:

Failed to Unmarshall: unexpected end of JSON input

Please note, that the identical behavior we are seeing across 3 OpenShift clusters. Container image has not been changed, but just the version of OpenShift (origin).

Please let me know if anyone has seen/experienced similar behavior as we have not found anything helpful or similar so far.