diff --git a/docs/samples/custom/kfserving-custom-model/requirements.txt b/docs/samples/custom/kfserving-custom-model/requirements.txt
index 33e0252..0352143 100644
--- a/docs/samples/custom/kfserving-custom-model/requirements.txt
+++ b/docs/samples/custom/kfserving-custom-model/requirements.txt
@@ -38,7 +38,7 @@ kfserving==0.3.0
 kubernetes==10.0.1
 MarkupSafe==1.1.1
 minio==5.0.7
-mistune==0.8.4
+mistune==2.0.3
 nbconvert==5.6.1
 nbformat==5.0.4
 notebook==6.0.3