GHSA-4GXV-P5G5-J7W7 gonic has arbitrary file write in createPlaylist: any authenticated user can write playlist M3U content to attacker-controlled path on the host

Summary A logic error in ServeCreateOrUpdatePlaylist allows any authenticated Subsonic user including non-admin to write playlist M3U content to an attacker-controlled absolute filesystem path on the gonic host, and to create intermediate directories with 0o777 permissions. The bug is independent...