diff --git a/requirements.txt b/requirements.txt
index f87f7fae..2f200d3d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,5 +14,5 @@ oslo.utils>=3.20.0 # Apache-2.0
 os-client-config>=1.28.0 # Apache-2.0
 osc-lib>=1.7.0 # Apache-2.0
 PrettyTable<0.8,>=0.7.1 # BSD
-cryptography>=1.6 # BSD/Apache-2.0
+cryptography!=2.0,>=1.6 # BSD/Apache-2.0
 decorator>=3.4.0 # BSD