diff --git a/requirements_dev.txt b/requirements_dev.txt
index a5dfa1a..3f4afbd 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -6,5 +6,5 @@ flake8==2.6.2
 tox==2.3.1
 coverage==4.1
 Sphinx>=1.4,<1.5
-cryptography==1.4
+cryptography==3.2
 PyYAML==3.11