Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to 39.8.10, 41.10.5, and 42.0.0-beta.2, Electron applications on macOS that use Squirrel.Mac-based automatic updates are vulnerable to a local race in the privileged ShipIt helper. The helper did not bind the validated update target to one canonical application-bundle path for the full installation, allowing a local attacker to redirect the root-level write so that it overwrites another application's files instead of the application that initiated the update. Applications on other platforms and macOS applications that do not use Squirrel.Mac-based automatic updates are not affected. This issue is fixed in versions 39.8.10, 41.10.5, and 42.0.0-beta.2.

Affected: npm: electron

### Impact

On macOS, Electron bundles the Squirrel.Mac auto-update framework, whose privileged `ShipIt` helper performs the final step of an update as root. A local attacker could cause that helper to overwrite a different application's files, as root, instead of the app that started the update. Exploitation requires local access to the machine.

Apps are only affected on macOS if they ship Squirrel.Mac-based auto-updates. Apps on other platforms, or that do not use Squirrel.Mac auto-updates, are not affected.

### Workarounds

There are no app side workarounds, you must update to a patched version of Electron.

### Fixed Versions

* `42.0.0-beta.2` * `41.10.5` * `39.8.10`

### For more information

If you have any questions or comments about this advisory, email us at [security@electronjs.org](mailto:security@electronjs.org)