Ryot is a self-hosted personal tracking application. Prior to 10.4.0, the createOrUpdateUserIntegration GraphQL mutation in crates/services/user/src/integration_operations.rs allows a low-privileged authenticated user to supply another user's integrationId to create_or_update_user_integration() without an ownership check. SeaORM treats the supplied primary key as an update target, and the operation assigns the caller's user_id while replacing the targeted integration's provider_specifics and other configuration, which can transfer ownership, overwrite configuration, or disable the victim's integration. Exploitation requires obtaining the victim's non-brute-forceable integration id, and the vulnerable update does not disclose existing stored credential values. This issue is fixed in version 10.4.0.