diff --git a/setup.py b/setup.py
index 5bd864d..848c29b 100644
--- a/setup.py
+++ b/setup.py
@@ -33,6 +33,6 @@
             'openapi-schema-validator ~= 0.1.5',
             'jsonschema ~= 3.0',
             # Newer versions are not compatible with our Flask version
-            'markupsafe == 2.0.1'
+            'markupsafe ==2.1.5'
       ],
       )