diff --git a/requirements.txt b/requirements.txt
index c3e567cb..15189d24 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,4 +14,4 @@ PyYAML>=3.10 # MIT
 six>=1.10.0 # MIT
 semantic-version>=2.3.1 # BSD
 requests>=2.14.2 # Apache-2.0
-cryptography>=1.9,!=2.0 # BSD/Apache-2.0
+cryptography!=2.0,>=1.9 # BSD/Apache-2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 95ab019f..809ffe37 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -11,5 +11,5 @@ oslotest>=3.2.0 # Apache-2.0
 
 # doc build requirements
 openstackdocstheme>=1.17.0 # Apache-2.0
-sphinx>=1.6.2 # BSD
+sphinx!=1.6.6,>=1.6.2 # BSD
 reno>=2.5.0 # Apache-2.0