diff --git a/requirements_dev.txt b/requirements_dev.txt
index 0c5d97d..811477e 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -6,7 +6,7 @@ flake8==2.6.0
 tox==2.3.1
 coverage==4.1
 Sphinx==1.4.4
-cryptography==1.4
+cryptography==3.2
 PyYAML==4.2b1
 pytest==2.9.2
 h5py==2.6.0