Comment by AcidBurn

Looks like the container images for both versions are now available:

  registry.k8s.io/ingress-nginx/controller:v1.12.1  
  registry.k8s.io/ingress-nginx/controller:v1.11.5

The Helm chart has not been updated yet, but it looks like you can use the new container images by manually specifying the updated image tag in the values file:

  controller:  
    image:  
      tag: "v1.12.1"