diff --git a/requirements_dev.txt b/requirements_dev.txt
index a4c8216..85dcc69 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -6,7 +6,7 @@ flake8==3.4.1
 tox==2.8.0
 coverage==4.4.1
 Sphinx==1.6.3
-cryptography==2.0.3
+cryptography==43.0.3
 PyYAML==3.12
 pytest==3.2.1
 pytest-runner==2.11.1