Kubernetes v1.19.16, v1.20.12 and v1.21.6 are now available in Rancher. They introduce new nginx-ingress image nginx-0.49.3-rancher1 to address CVE-2021-25742 - Ingress-nginx custom snippets allows retrieval of ingress-nginx serviceaccount token and secrets across all namespaces.
Kubernetes v1.19.16 is now available for Rancher versions v2.5.11+
Kubernetes v1.20.12 is now available for Rancher versions v2.5.11+
Kubernetes v1.21.6 is now available for Rancher versions v2.6.2+
Note : If you are an air gapped user, please review the documentation on how to get these versions