diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index b70e285..aca03fd 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -599,11 +599,32 @@
         assert_python_ok('-c', code)
 
 
-class ExecvpeTests(unittest.TestCase):
+class ExecTests(unittest.TestCase):
 
     def test_execvpe_with_bad_arglist(self):
         self.assertRaises(ValueError, os.execvpe, 'notepad', [], None)
 
+    def test_execve_invalid_env(self):
+        args = [sys.executable, '-c', 'pass']
+
+        # null character in the enviroment variable name
+        newenv = os.environ.copy()
+        newenv["FRUIT\0VEGETABLE"] = "cabbage"
+        with self.assertRaises(TypeError):
+            os.execve(args[0], args, newenv)
+
+        # null character in the enviroment variable value
+        newenv = os.environ.copy()
+        newenv["FRUIT"] = "orange\0VEGETABLE=cabbage"
+        with self.assertRaises(TypeError):
+            os.execve(args[0], args, newenv)
+
+        # equal character in the enviroment variable name
+        newenv = os.environ.copy()
+        newenv["FRUIT=ORANGE"] = "lemon"
+        with self.assertRaises(ValueError):
+            os.execve(args[0], args, newenv)
+
 
 @unittest.skipUnless(sys.platform == "win32", "Win32 specific tests")
 class Win32ErrorTests(unittest.TestCase):
@@ -879,6 +900,62 @@
         self._kill_with_event(signal.CTRL_BREAK_EVENT, "CTRL_BREAK_EVENT")
 
 
+class SpawnTests(unittest.TestCase):
+    def _test_invalid_env(self, spawn):
+        args = [sys.executable, '-c', 'pass']
+
+        # null character in the enviroment variable name
+        newenv = os.environ.copy()
+        newenv["FRUIT\0VEGETABLE"] = "cabbage"
+        try:
+            exitcode = spawn(os.P_WAIT, args[0], args, newenv)
+        except TypeError:
+            pass
+        else:
+            self.assertEqual(exitcode, 127)
+
+        # null character in the enviroment variable value
+        newenv = os.environ.copy()
+        newenv["FRUIT"] = "orange\0VEGETABLE=cabbage"
+        try:
+            exitcode = spawn(os.P_WAIT, args[0], args, newenv)
+        except TypeError:
+            pass
+        else:
+            self.assertEqual(exitcode, 127)
+
+        # equal character in the enviroment variable name
+        newenv = os.environ.copy()
+        newenv["FRUIT=ORANGE"] = "lemon"
+        try:
+            exitcode = spawn(os.P_WAIT, args[0], args, newenv)
+        except ValueError:
+            pass
+        else:
+            self.assertEqual(exitcode, 127)
+
+        # equal character in the enviroment variable value
+        filename = test_support.TESTFN
+        self.addCleanup(test_support.unlink, filename)
+        with open(filename, "w") as fp:
+            fp.write('import sys, os\n'
+                     'if os.getenv("FRUIT") != "orange=lemon":\n'
+                     '    raise AssertionError')
+        args = [sys.executable, filename]
+        newenv = os.environ.copy()
+        newenv["FRUIT"] = "orange=lemon"
+        exitcode = spawn(os.P_WAIT, args[0], args, newenv)
+        self.assertEqual(exitcode, 0)
+
+    @unittest.skipUnless(hasattr(os, 'spawnve'), 'test needs os.spawnve()')
+    def test_spawnve_invalid_env(self):
+        self._test_invalid_env(os.spawnve)
+
+    @unittest.skipUnless(hasattr(os, 'spawnvpe'), 'test needs os.spawnvpe()')
+    def test_spawnvpe_invalid_env(self):
+        self._test_invalid_env(os.spawnvpe)
+
+
 def test_main():
     test_support.run_unittest(
         FileTests,
@@ -890,11 +967,12 @@
         DevNullTests,
         URandomTests,
         URandomFDTests,
-        ExecvpeTests,
+        ExecTests,
         Win32ErrorTests,
         TestInvalidFD,
         PosixUidGidTests,
-        Win32KillTests
+        Win32KillTests,
+        SpawnTests,
     )
 
 if __name__ == "__main__":
diff --git a/Lib/test/test_posix.py b/Lib/test/test_posix.py
index e0c84f2..f1626b7 100644
--- a/Lib/test/test_posix.py
+++ b/Lib/test/test_posix.py
@@ -504,6 +504,15 @@
         finally:
             posix.lchflags(_DUMMY_SYMLINK, dummy_symlink_st.st_flags)
 
+    @unittest.skipUnless(hasattr(os, "putenv"), "requires os.putenv()")
+    def test_putenv(self):
+        with self.assertRaises(TypeError):
+            os.putenv('FRUIT\0VEGETABLE', 'cabbage')
+        with self.assertRaises(TypeError):
+            os.putenv('FRUIT', 'orange\0VEGETABLE=cabbage')
+        with self.assertRaises(ValueError):
+            os.putenv('FRUIT=ORANGE', 'lemon')
+
     @unittest.skipUnless(hasattr(posix, 'getcwd'),
                          'test needs posix.getcwd()')
     def test_getcwd_long_pathnames(self):