diff --git a/src/yunohost/app.py b/src/yunohost/app.py
index 302049ed8..5f5d9f8f9 100644
--- a/src/yunohost/app.py
+++ b/src/yunohost/app.py
@@ -97,6 +97,9 @@ def app_fetchlist(url=None, name=None):
         name -- Name of the list
         url -- URL of remote JSON list
     """
+    if not url.endswith(".json"):
+        raise YunohostError("This is not a valid application list url. It should end with .json.")
+
     # If needed, create folder where actual appslists are stored
     if not os.path.exists(REPO_PATH):
         os.makedirs(REPO_PATH)