Electron: DevTools JavaScript Injection via Unsanitized Dock State Parameter

Impact

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.

Apps are only affected if untrusted input can reach the mode argument of openDevTools(), or if untrusted content can call openDevTools() on a <webview> it embeds. Apps that only ever pass a fixed dock mode are not affected.

Workarounds

Only pass fixed, allowlisted values (right, bottom, undocked, detach) as the DevTools mode, and do not expose openDevTools to untrusted content.

Fixed Versions

• 42.0.0-beta.1
• 41.2.0
• 40.9.0
• 39.8.7

For more information

If you have any questions or comments about this advisory, email Electron at security@electronjs.org