Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.7, 40.9.0, 41.2.0, and 42.0.0-beta.1, the mode option of webContents.openDevTools() was not sanitized before use by the DevTools frontend. If an attacker can influence this value, script under their control may run in the DevTools context, which in unsandboxed configurations has access to Node.js, including when untrusted input reaches the mode argument of openDevTools() or untrusted content calls openDevTools() on a webview it embeds. This issue is fixed in 39.8.7, 40.9.0, 41.2.0, and 42.0.0-beta.1.

Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.10, 40.9.3, 41.4.0, and 42.0.0, a custom scheme registered with supportFetchAPI: true but without corsEnabled: true was not subject to CORS enforcement. A page loaded from a remote origin could therefore fetch() or XMLHttpRequest that scheme cross-origin and read the full response body, rather than the read being blocked. Apps that serve sensitive data from such a scheme and load remote or untrusted content in a renderer are affected. This issue is fixed in versions 39.8.10, 40.9.3, 41.4.0, and 42.0.0.