diff --git a/requirements-demo.txt b/requirements-demo.txt
index 0643b5c..324b18c 100644
--- a/requirements-demo.txt
+++ b/requirements-demo.txt
@@ -3,3 +3,5 @@ datasketch>=1.5.1
 conllu>=4.2.1
 matplotlib>=3.3.3
 mmh3>=3.0.0
+jupyter-server>=2.14.1 # not directly required, pinned by Snyk to avoid a vulnerability
+tornado>=6.4.1 # not directly required, pinned by Snyk to avoid a vulnerability