diff --git a/requirements_dev.txt b/requirements_dev.txt
index 3fda6ac..f9f4c14 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,7 +7,7 @@ tox==2.9.1
 coverage==4.5.1
 Sphinx==1.6.5
 twine==1.9.1
-cryptography==2.1.4
+cryptography==3.2
 PyYAML==3.11
 pytest==3.3.2
 pytest-runner==2.11.1