diff --git a/definitions/parser.py b/definitions/parser.py
index a689193..45a3a60 100644
--- a/definitions/parser.py
+++ b/definitions/parser.py
@@ -281,8 +281,8 @@ def _load(source):
         """Load a YAML file or string."""
         if source and os.path.isfile(source):
             with open(source) as file_:
-                return yaml.load(file_)
-        return yaml.load(source)
+                return yaml.safe_load(file_)
+        return yaml.safe_load(source)
 
     @staticmethod
     def _find_type(module, name):