diff --git a/tests_tf/test_attacks.py b/tests_tf/test_attacks.py
index 23d73ab90..17d4177ee 100644
--- a/tests_tf/test_attacks.py
+++ b/tests_tf/test_attacks.py
@@ -851,7 +851,7 @@ def test_attack_strength(self):
 
     orig_labs = np.argmax(self.sess.run(self.model.get_logits(x_val)), axis=1)
     new_labs = np.argmax(self.sess.run(self.model.get_logits(x_adv)), axis=1)
-    self.assertLess(np.mean(orig_labs == new_labs), 0.4)
+    self.assertLess(np.mean(orig_labs == new_labs), 0.5)
     self.assertGreater(np.mean(orig_labs == new_labs), 0.2)
 
   def test_grad_clip(self):
@@ -1711,4 +1711,4 @@ def test_generate_targeted_l2(self):
 
     new_labs = np.argmax(self.sess.run(self.model.get_logits(x_adv)), axis=1)
     self.assertTrue(np.mean(np.argmax(y_target, axis=1) == new_labs)
-                    > 0.9)
\ No newline at end of file
+                    > 0.9)