Node.js took JavaScript from the browser to server-side web applications, and injection vulnerabilities are now commonly reported in Node.js modules. However, existing taint analysis approaches for JavaScript are brittle, require extensive manual modelling, and fail to analyse simple Node.js applications. For this reason, we developed AFFOGATO, a robust and practical grey-box taint analysis tool that uses black-box reasoning to overcome the need for manual modellingwhile using white-box program analysis to reason about critical program operations. We evaluate AFFOGATO on a suite of Node.js modules and show how it can detect all publicly disclosed injection vulnerabilities with an acceptable overhead, outperforming the existing state-of-the-art tool for Node.js.