diff --git a/lower-constraints.txt b/lower-constraints.txt
index dcdbc34c..41f63431 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -7,7 +7,7 @@ cffi==1.7.0
 cliff==2.8.0
 cmd2==0.8.0
 coverage==4.0
-cryptography==1.9
+cryptography==2.1
 debtcollector==1.2.0
 docutils==0.11
 dulwich==0.15.0
diff --git a/requirements.txt b/requirements.txt
index 1f490b24..a6020f71 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@
 
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
 Babel!=2.4.0,>=2.3.4 # BSD
-cryptography!=2.0,>=1.9 # BSD/Apache-2.0
+cryptography>=2.1 # BSD/Apache-2.0
 python-barbicanclient>=4.5.2 # Apache-2.0
 oslo.config>=5.2.0 # Apache-2.0
 oslo.context>=2.19.2 # Apache-2.0