diff --git a/requirements_dev.txt b/requirements_dev.txt
index 97d8654..ccb87c1 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -5,6 +5,6 @@ watchdog==0.8.3
 flake8==3.3.0
 tox==2.7.0
 Sphinx==1.5.5
-cryptography==1.8.1
+cryptography==42.0.5
 PyYAML==3.12
 twine==1.9.1