diff --git a/ch2_minimal_flask_server/requirements.txt b/ch2_minimal_flask_server/requirements.txt
index 1802437..e3e959f 100644
--- a/ch2_minimal_flask_server/requirements.txt
+++ b/ch2_minimal_flask_server/requirements.txt
@@ -1,4 +1,4 @@
-certifi==2021.10.8
+certifi==2022.12.7
 chardet==4.0.0
 charset-normalizer==2.0.11
 click==8.0.3