diff --git a/ajour-sync/server/pyproject.toml b/ajour-sync/server/pyproject.toml
index 6542152..3172648 100644
--- a/ajour-sync/server/pyproject.toml
+++ b/ajour-sync/server/pyproject.toml
@@ -6,7 +6,7 @@ authors = ["Henrik Steen <henrist@henrist.net>"]
 
 [tool.poetry.dependencies]
 python = "^3.8"
-Flask = "^1.1.1"
+Flask = "^2.0.0"
 gunicorn = "^20.0.4"
 
 [tool.poetry.dev-dependencies]