Helm requires that kubelet have access to a copy of the `socat` program to proxy connections to the Tiller API. On Container Linux the Kubelet runs inside of a [hyperkube](https://github.com/kubernetes/kubernetes/tree/master/cluster/images/hyperkube) container image that has socat. So, even though Container Linux doesn't ship `socat` the container filesystem running kubelet does have socat. To learn more read the [Kubelet Wrapper](https://coreos.com/kubernetes/docs/latest/kubelet-wrapper.html) docs.