diff --git a/requirements-demo.txt b/requirements-demo.txt
index 14cbe82..dfd4ae6 100644
--- a/requirements-demo.txt
+++ b/requirements-demo.txt
@@ -4,3 +4,4 @@ pandas>=1.1.5
 matplotlib>=1.15.0
 numpy>=1.22.2 # not directly required, pinned by Snyk to avoid a vulnerability
 setuptools>=65.5.1 # not directly required, pinned by Snyk to avoid a vulnerability
+tornado>=6.3.2 # not directly required, pinned by Snyk to avoid a vulnerability