diff --git a/requirements.txt b/requirements.txt
index bc70cc2..0c05e98 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,3 +4,4 @@ syft-tensorflow==0.1.0
 jupyter==1.0.0
 tensorflow-datasets==1.3.0
 
+mistune>=2.0.1 # not directly required, pinned by Snyk to avoid a vulnerability