diff --git a/chap09/blue/requirements.txt b/chap09/blue/requirements.txt
index 9ea73e7..d9db5c5 100644
--- a/chap09/blue/requirements.txt
+++ b/chap09/blue/requirements.txt
@@ -1,2 +1,2 @@
-Flask==1.0
+Flask==2.3.2
 gunicorn==19.7.0