diff --git a/homeassistant/package_constraints.txt b/homeassistant/package_constraints.txt
index 70fb519eef4ee..3e9a763181a2c 100644
--- a/homeassistant/package_constraints.txt
+++ b/homeassistant/package_constraints.txt
@@ -13,6 +13,8 @@ pyyaml>=3.13,<4
 requests==2.19.1
 voluptuous==0.11.5
 
+pycryptodome>=3.6.6
+
 # Breaks Python 3.6 and is not needed for our supported Python versions
 enum34==1000000000.0.0
 
diff --git a/script/gen_requirements_all.py b/script/gen_requirements_all.py
index fe23e638e5b76..4b694ec7ec071 100755
--- a/script/gen_requirements_all.py
+++ b/script/gen_requirements_all.py
@@ -124,6 +124,8 @@
 CONSTRAINT_PATH = os.path.join(os.path.dirname(__file__),
                                '../homeassistant/package_constraints.txt')
 CONSTRAINT_BASE = """
+pycryptodome>=3.6.6
+
 # Breaks Python 3.6 and is not needed for our supported Python versions
 enum34==1000000000.0.0