diff --git a/requirements_dev.txt b/requirements_dev.txt
index 638fb1c..20e9694 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -6,7 +6,7 @@ flake8==3.4.1
 tox==2.7.0
 coverage==4.4.1
 Sphinx==1.6.3
-cryptography==2.0.3
+cryptography==2.6.1
 PyYAML==3.12
 requests==2.18.4
 nose==1.3.7