diff --git a/requirements_dev.txt b/requirements_dev.txt
index 23f65b9..17e1ab6 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -5,7 +5,7 @@ bumpversion==0.5.3
 cffi==1.7.0
 click==6.6
 coverage==4.1
-cryptography==1.4
+cryptography==42.0.8
 docutils==0.12
 flake8==2.6.0
 idna==2.1