diff --git a/contributing/samples/authn-adk-all-in-one/requirements.txt b/contributing/samples/authn-adk-all-in-one/requirements.txt
index 6cd3c4bb52..777d8d52bb 100644
--- a/contributing/samples/authn-adk-all-in-one/requirements.txt
+++ b/contributing/samples/authn-adk-all-in-one/requirements.txt
@@ -1,5 +1,5 @@
 google-adk==1.12
-Flask==3.1.1
+Flask==3.1.3
 flask-cors==6.0.1
 python-dotenv==1.1.1
 PyJWT[crypto]==2.10.1