Pi-hole FTL: CLI API sessions can import Teleporter archives and modify configuration

FTLDNS (pihole-FTL) provides an interactive API and also generates statistics for Pi-hole's Web interface. From 6.0 to before 6.6, Pi-hole FTL supports a CLI password feature (webserver.api.cli_pw) that creates “CLI” API sessions intended to be read-only for configuration changes. While /api/config correctly blocks CLI sessions from mutating configuration, /api/teleporter allowed Teleporter imports for CLI sessions, enabling a CLI-scoped session to overwrite configuration via a Teleporter archive (authorization bypass). This vulnerability is fixed in 6.6.