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.