diff --git a/requirements_dev.txt b/requirements_dev.txt
index 5330a30..c76625d 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -6,6 +6,6 @@ flake8==3.0.4
 tox==2.3.1
 coverage==4.2
 Sphinx==1.4.6
-cryptography==1.5
+cryptography==1.5.1
 PyYAML==3.12
 requests>=2.10.0