diff --git a/pytest-godber/requirements-2017.txt b/pytest-godber/requirements-2017.txt
index 101ebbc..0ccd059 100644
--- a/pytest-godber/requirements-2017.txt
+++ b/pytest-godber/requirements-2017.txt
@@ -20,7 +20,7 @@ jupyter-client==5.1.0
 jupyter-console==5.2.0
 jupyter-core==4.3.0
 MarkupSafe==1.0
-mistune==0.7.4
+mistune==0.8.1
 nbconvert==5.3.1
 nbformat==4.4.0
 notebook==5.1.0