diff --git a/doc/requirements.txt b/doc/requirements.txt
index 4179db2..082702d 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,6 +1,6 @@
 Babel==2.8.0
 click==7.1.1
-Flask==0.12.2
+Flask==2.3.2
 Flask-Babel==0.11.2
 Frozen-Flask==0.15
 itsdangerous==1.1.0