diff --git a/requirements_frozen.txt b/requirements_frozen.txt
index e0756e6..950d4cf 100644
--- a/requirements_frozen.txt
+++ b/requirements_frozen.txt
@@ -19,7 +19,7 @@ jsonschema==2.5.1
 jupyter-client==4.4.0
 jupyter-core==4.2.1
 matplotlib==1.5.3
-mistune==0.8.1
+mistune==2.0.3
 multipledispatch==0.4.9
 nbconvert==4.2.0
 nbformat==4.2.0