CVE-2026-54494
MediumCVSS 5.3Summary
Koel before version 9.7.1 incorrectly treats NAT64 and 6to4 addresses as public, allowing an authenticated user to place such an address in a podcast RSS and trigger requests to internal services or cloud metadata. The response body is returned to the user.
Risk Assessment
An attacker can access internal resources or sensitive data (e.g., cloud metadata), potentially leading to privilege escalation or data leakage.
Recommendation
Update Koel to version 9.7.1, which fixes the address validation in isPublicHost().
Original NVD description (English source)
Koel is a free, open-source music streaming solution. Prior to 9.7.1, App\Helpers\Network::isPublicHost() uses filter_var() with FILTER_FLAG_NO_PRIV_RANGE and FILTER_FLAG_NO_RES_RANGE, which treats NAT64 64:ff9b::/96 and 6to4 2002::/16 wrappers of private, loopback, or link-local IPv4 addresses as public. An authenticated user can place such an address in a podcast RSS <enclosure url> and reach app/Values/Podcast/EpisodePlayable.php through EpisodePlayable::createForEpisode(), where isSafeUrl() accepts the target and Http::sink($file)->get($url) fetches it. On a host with NAT64 or 6to4 routing, Koel can request internal services or cloud metadata and return the response body to the user. This issue is fixed in version 9.7.1