diff --git a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go
index 066626252b71..05813fc926a3 100644
--- a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go
+++ b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go
@@ -230,6 +230,10 @@ func (in *KubeadmControlPlane) validateCommon() (allErrs field.ErrorList) {
 }
 
 func (in *KubeadmControlPlane) validateEtcd(prev *KubeadmControlPlane) (allErrs field.ErrorList) {
+	if in.Spec.KubeadmConfigSpec.ClusterConfiguration == nil {
+		return allErrs
+	}
+
 	if in.Spec.KubeadmConfigSpec.ClusterConfiguration.Etcd.External != nil && prev.Spec.KubeadmConfigSpec.ClusterConfiguration.Etcd.Local != nil {
 		allErrs = append(
 			allErrs,
diff --git a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go
index dfa3e05b762e..d3347aebab7c 100644
--- a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go
+++ b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go
@@ -296,6 +296,9 @@ func TestKubeadmControlPlaneValidateUpdate(t *testing.T) {
 		},
 	}
 
+	withoutClusterConfiguration := before.DeepCopy()
+	withoutClusterConfiguration.Spec.KubeadmConfigSpec.ClusterConfiguration = nil
+
 	tests := []struct {
 		name      string
 		expectErr bool
@@ -476,6 +479,12 @@ func TestKubeadmControlPlaneValidateUpdate(t *testing.T) {
 			before:    beforeInvalidEtcdCluster,
 			kcp:       afterInvalidEtcdCluster,
 		},
+		{
+			name:      "should pass if ClusterConfiguration is nil",
+			expectErr: false,
+			before:    withoutClusterConfiguration,
+			kcp:       withoutClusterConfiguration,
+		},
 	}
 
 	for _, tt := range tests {