The Vue.js Devtools extension was found to leak screenshot data back to a malicious web page via the standard `postMessage()` API. By creat…

The Vue.js Devtools extension was found to leak screenshot data back to a malicious web page via the standard `postMessage()` API. By creating a malicious web page with an iFrame targeting a sensitive resource (i.e. a locally accessible file or sensitive website), and registering a listener on the web page, the extension sent messages back to the listener, containing the base64 encoded screenshot data of the sensitive resource.