var express = require('express'); var app = express(); var myObj = {} app.get('/user/:id', function(req, res) { myCoolLocalFct(req.query.userControlled); var prop = myCoolLocalFct(req.query.userControlled); // $ Source myObj[prop] = 23; // $ Alert myObj.prop = 23; var x = myObj[prop]; // OK - flagged by different query x(23); delete myObj[prop]; // $ Alert Object.defineProperty(myObj, prop, {value: 24}); // $ Alert var headers = {}; headers[prop] = 42; // $ Alert res.set(headers); myCoolLocalFct[req.query.x](); // OK - flagged by method name injection }); function myCoolLocalFct(x) { var result = x; return result.substring(0, result.length); }