diff --git a/signer/core/apitypes/types.go b/signer/core/apitypes/types.go
index b5fd5a2854..dcbd04867c 100644
--- a/signer/core/apitypes/types.go
+++ b/signer/core/apitypes/types.go
@@ -544,7 +544,7 @@ func parseBytes(encType interface{}) ([]byte, bool) {
 	// Handle array types.
 	val := reflect.ValueOf(encType)
 	if val.Kind() == reflect.Array && val.Type().Elem().Kind() == reflect.Uint8 {
-		v := reflect.MakeSlice(reflect.TypeOf([]byte{}), val.Len(), val.Len())
+		v := reflect.ValueOf(make([]byte, val.Len()))
 		reflect.Copy(v, val)
 		return v.Bytes(), true
 	}