diff --git a/python/ql/lib/semmle/python/frameworks/Flask.qll b/python/ql/lib/semmle/python/frameworks/Flask.qll
index 1cf7d2573f8..13715199513 100644
--- a/python/ql/lib/semmle/python/frameworks/Flask.qll
+++ b/python/ql/lib/semmle/python/frameworks/Flask.qll
@@ -421,9 +421,7 @@ module Flask {
 
   /** An `FileStorage` instance that originates from a flask request. */
   private class FlaskRequestFileStorageInstances extends Werkzeug::FileStorage::InstanceSource {
-    FlaskRequestFileStorageInstances() {
-      this = requestFileStorage().getAValueReachableFromSource()
-    }
+    FlaskRequestFileStorageInstances() { this = requestFileStorage().asSource() }
   }
 
   /** An `Headers` instance that originates from a flask request. */