diff --git a/requirements.txt b/requirements.txt
index 1c819217f..9cef063da 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 netaddr>=0.7.6
 PyYAML>=3.10
 docutils>=0.11
-pyOpenSSL
-cryptography
+cryptography!=1.2.2,>=1.0
+pyOpenSSL<15.0.0
diff --git a/setup.py b/setup.py
index d8c39c11c..04f58b051 100644
--- a/setup.py
+++ b/setup.py
@@ -104,7 +104,8 @@ setup(
     include_package_data=True,
     long_description=read('README.md'),
     zip_safe=False,
-    install_requires=['netaddr', 'pyOpenSSL', 'PyYAML', 'docutils'],
+    install_requires=['netaddr>=0.7.6', 'pyOpenSSL<15.0.0', 'PyYAML>=3.10',
+                      'docutils>=0.11', 'cryptography<=1.2.2,>=1.0'],
     classifiers=[
         "Development Status :: 3 - Alpha",
         "Topic :: Utilities",