diff --git a/requirements-optional.txt b/requirements-optional.txt
index 27fe558..f95e9cb 100644
--- a/requirements-optional.txt
+++ b/requirements-optional.txt
@@ -1,4 +1,4 @@
-Flask==0.9
+Flask==2.3.2
 Twisted==10.2.0
 bottle==0.11.6
 tornado==2.2.1