Syntax errors: Use the BaseLoader for safety

yamllint/__init__.py

@@ -58,7 +58,7 @@ def get_costemic_problems(buffer, conf):
 
 def get_syntax_error(buffer):
     try:
-        list(yaml.parse(buffer))
+        list(yaml.parse(buffer, Loader=yaml.BaseLoader))
     except yaml.error.MarkedYAMLError as e:
         problem = LintProblem(e.problem_mark.line + 1,
                               e.problem_mark.column + 1,