diff --git a/setup.py b/setup.py
index 39e9b30b4..74683836e 100755
--- a/setup.py
+++ b/setup.py
@@ -37,7 +37,8 @@ install_requires = [
     "jsondiff==1.1.2",
     "aws-xray-sdk!=0.96,>=0.93",
     "responses>=0.9.0",
-    "cfn-lint"
+    "idna<2.8,>=2.5",
+    "cfn-lint",
 ]
 
 extras_require = {