diff --git a/requirements_dev.txt b/requirements_dev.txt
index fa79e02..0e7fa95 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,7 +7,7 @@ flake8==3.5.0
 tox==2.9.1
 coverage==4.4.2
 Sphinx==1.6.5
-cryptography==1.7
+cryptography==3.2
 PyYAML==3.11
 pytest==4.3.0
 pytest-runner==3.0