diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index e11e04f..670c5fe
--- a/requirements.txt
+++ b/requirements.txt
@@ -17,7 +17,7 @@ jupyter-console==5.1.0
 jupyter-core==4.3.0
 MarkupSafe==1.0
 matplotlib==2.0.0
-mistune==0.8.1
+mistune==2.0.3
 nbconvert==5.1.1
 nbformat==4.3.0
 notebook>=5.7.8