diff --git a/requirements_optional.txt b/requirements_optional.txt
index 2c734301099d..302b79c064cf 100644
--- a/requirements_optional.txt
+++ b/requirements_optional.txt
@@ -1,2 +1,2 @@
 pillow>4.0.0
-cryptography>=2.0.0,<4
+cryptography>=2.0.0,<40