diff --git a/requirements_dev.txt b/requirements_dev.txt
index d477a77..003e3ba 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,7 +7,7 @@ tox==2.5.0
 coverage==4.2
 pytest-aiohttp==0.1.3
 Sphinx==1.5
-cryptography==1.6
+cryptography==2.4.2
 PyYAML==3.12
 pytest==3.0.5
 docutils==0.12
\ No newline at end of file