diff --git a/requirements.in b/requirements.in
index 26142703f..e3706e083 100644
--- a/requirements.in
+++ b/requirements.in
@@ -1,6 +1,8 @@
 certifi==2024.7.4
 Click==8.1.7
 Flask==2.2.5
+# Flask 2.2.x test_client uses werkzeug.__version__, removed in Werkzeug 3.1.
+Werkzeug==3.0.6
 Flask-Babel==3.1.0
 Flask-Cors==6.0.0
 Flask-Login==0.6.3
diff --git a/requirements.txt b/requirements.txt
index 198e05128..d2ee198a5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -907,10 +907,11 @@ urllib3==2.7.0 \
     --hash=sha256:231e0ec3b63ceb14667c67be60f2f2c40a518cb38b03af60abc813da26505f4c \
     --hash=sha256:9fb4c81ebbb1ce9531cce37674bbc6f1360472bc18ca9a553ede278ef7276897
     # via requests
-werkzeug==3.0.3 \
-    --hash=sha256:097e5bfda9f0aba8da6b8545146def481d06aa7d3266e7448e2cccf67dd8bd18 \
-    --hash=sha256:fc9645dc43e03e4d630d23143a04a7f947a9a3b5727cd535fdfe155a17cc48c8
+werkzeug==3.0.6 \
+    --hash=sha256:1bc0c2310d2fbb07b1dd1105eba2f7af72f322e1e455f2f93c993bee8c8a5f17 \
+    --hash=sha256:a8dd59d4de28ca70471a34cba79bed5f7ef2e036a76b3ab0835474246eb41f8d
     # via
+    #   -r requirements.in
     #   flask
     #   flask-cors
     #   flask-login