diff --git a/ch13/requirements/requirements.txt b/ch13/requirements/requirements.txt
index 18b3bdb..64c4498 100644
--- a/ch13/requirements/requirements.txt
+++ b/ch13/requirements/requirements.txt
@@ -292,7 +292,7 @@ terminado==0.18.1
     #   jupyter-server-terminals
 tinycss2==1.4.0
     # via bleach
-tornado==6.5.7
+tornado==6.5.8
     # via
     #   ipykernel
     #   jupyter-client