Error creating ca-config.json: invalid argument

[iocanel]

I am trying to install the operator in a local Openshift v3.11 cluster and it fails to start the cluster (see the logs below).

The steps I am using to install are:

oc new-project operator
oc create -f example/controller.yaml
oc create -f example/host-pat-sc.yaml
oc create -f example/es-cluster-hostpath.yaml

The operator is succesfully installed, but the cluster is not.
In the operator logs I see the following:

time="2019-04-08T11:15:36Z" level=info msg="Found 0 existing clusters "
time="2019-04-08T11:15:36Z" level=info msg="Watching for elasticsearch events..."
time="2019-04-08T11:16:25Z" level=info msg="Process Elasticsearch Event ADDED"
time="2019-04-08T11:16:25Z" level=info msg="--------> Received ElasticSearch Event!"
time="2019-04-08T11:16:25Z" level=info msg="Found cluster: example-es-cluster"
time="2019-04-08T11:16:25Z" level=info msg="use-ssl not specified, defaulting to UseSSL=true"
time="2019-04-08T11:16:25Z" level=info msg="Using [upmcenterprises/docker-elasticsearch-kubernetes:6.1.3_1] as image for es cluster"
time="2019-04-08T11:16:25Z" level=info msg="use-ssl not specified, defaulting to UseSSL=true"
time="2019-04-08T11:16:25Z" level=info msg="Creating new certs!"
time="2019-04-08T11:16:25Z" level=error msg="Error creating ca-config.json: invalid argument"
time="2019-04-08T11:16:25Z" level=error msg="invalid argument"
time="2019-04-08T11:16:25Z" level=error msg="invalid argument"

My understanding is that I could work around the issue by providing my own secret containing the certificates. Please provide more details on how such secret can be created.