diff --git a/Lib/test/test_pwd.py b/Lib/test/test_pwd.py
index c789326425be32..aa090b464a7222 100644
--- a/Lib/test/test_pwd.py
+++ b/Lib/test/test_pwd.py
@@ -59,6 +59,8 @@ def test_errors(self):
         self.assertRaises(TypeError, pwd.getpwnam)
         self.assertRaises(TypeError, pwd.getpwnam, 42)
         self.assertRaises(TypeError, pwd.getpwall, 42)
+        # embedded null character
+        self.assertRaisesRegex(ValueError, 'null', pwd.getpwnam, 'a\x00b')
 
         # try to get some errors
         bynames = {}