diff --git a/contrib/aws/cloudformation-ec2-efs.yaml b/contrib/aws/cloudformation-ec2-efs.yaml
index 781f3dd3c..2bb7d9fde 100644
--- a/contrib/aws/cloudformation-ec2-efs.yaml
+++ b/contrib/aws/cloudformation-ec2-efs.yaml
@@ -159,7 +159,7 @@ Resources:
             mount -a -t efs defaults
 
             # Create/update the config & password files.
-            mkdir "$BASE/conf" -p
+            [[ -d "$BASE/conf" ]] || mkdir "$BASE/conf"
             curl -o "$BASE/conf/htpasswd" "${VerdaccioHtpasswdUrl}"
             curl -o "$BASE/conf/config.yaml" "${VerdaccioConfigUrl}"