diff --git a/django/contrib/auth/hashers.py b/django/contrib/auth/hashers.py
index 7658379871..6cd57f197a 100644
--- a/django/contrib/auth/hashers.py
+++ b/django/contrib/auth/hashers.py
@@ -602,6 +602,7 @@ class CryptPasswordHasher(BasePasswordHasher):
         crypt = self._load_library()
         assert len(salt) == 2
         data = crypt.crypt(force_str(password), salt)
+        assert data is not None  # A platform like OpenBSD with a dummy crypt module.
         # we don't need to store the salt, but Django used to do this
         return "%s$%s$%s" % (self.algorithm, '', data)
 
diff --git a/tests/auth_tests/test_hashers.py b/tests/auth_tests/test_hashers.py
index a43c170ec1..845deee646 100644
--- a/tests/auth_tests/test_hashers.py
+++ b/tests/auth_tests/test_hashers.py
@@ -19,6 +19,10 @@ try:
     import crypt
 except ImportError:
     crypt = None
+else:
+    # On some platforms (e.g. OpenBSD), crypt.crypt() always return None.
+    if crypt.crypt('', '') is None:
+        crypt = None
 
 try:
     import bcrypt