In Electron before versions 11.0.0-beta.1, 10.0.1, 9.3.0 or 8.5.1 the `will-navigate` event that apps use to prevent navigations to unexpected destinations as per our security recommendations can be bypassed when a sub-frame performs a top-frame navigation across sites. The issue is patched in versions 11.0.0-beta.1, 10.0.1, 9.3.0 or 8.5.1 As a workaround sandbox all your iframes using the sandbox attribute. This will prevent them creating top-frame navigations and is good practice anyway.