For serial-port and media (camera / microphone) permission checks made from an iframe, the requestingOrigin passed to session.setPermissionCheckHandler was the top-level frame's origin rather than the requesting frame's. Origin-based handler logic could therefore grant a cross-origin iframe device access intended only for the top-level origin.

Apps are only affected if they use setPermissionCheckHandler with origin-based logic and embed cross-origin iframes with delegated device permissions. Apps that base the decision on details.securityOrigin, or that do not embed such iframes, are not affected.

Check details.securityOrigin instead of requestingOrigin for these permissions, or do not delegate device permissions to untrusted iframes.

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