# CVE-2026-54494: Koel SSRF via IPv6 transition address bypass in isPublicHost

Source: https://junglewise.ai/threats/cve-2026-54494-koel-ssrf-via-ipv6-transition-address-bypass-in-ispublichost  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-19. Updated: 2026-07-15  
License: CC BY 4.0 with a link back

CVE-2026-54494 · Severity: medium · CVSS 4 · Published 2026-08-19

Koel, a personal music streaming server, is vulnerable to a security flaw where an attacker can trick the server into accessing internal network resources. By providing a specially crafted podcast feed URL, an authenticated user can bypass security filters and view sensitive data from internal services or cloud metadata endpoints. This could lead to the exposure of private information or cloud credentials that are not intended to be accessible from the internet.

Technologies: [phanan/koel (Packagist)](https://junglewise.ai/threats/technologies/phanan-koel), [Phanan Koel](https://junglewise.ai/threats/technologies/koel). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist), [Phanan](https://junglewise.ai/threats/vendors/phanan).

## Quick answers

**Is CVE-2026-54494 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-54494 being exploited in the wild.

**How severe is CVE-2026-54494?** Medium severity, with a CVSS score of 4, published 19 August 2026.

**Which products and versions are affected?** phanan/koel (Packagist) <= 9.7.0, ECOSYSTEM:introduced=0,fixed=9.7.1; Phanan Koel <= 9.7.0.

**Is there a fix for CVE-2026-54494?** Yes. phanan/koel (Packagist): upgrade to 9.7.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-54494 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-54494?** Check whether you run phanan/koel (Packagist) or Phanan Koel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- phanan/koel (Packagist): upgrade to 9.7.1 or later

  ```sh
  composer require phanan/koel:^9.7.1
  ```


## Technical details

A Server-Side Request Forgery (SSRF) vulnerability exists in Koel's podcast enclosure processing. The `App\Helpers\Network::isPublicHost()` method uses PHP's `filter_var` with `FILTER_FLAG_NO_PRIV_RANGE` and `FILTER_FLAG_NO_RES_RANGE`, which fails to identify IPv6 transition prefixes like NAT64 (64:ff9b::/96) and 6to4 (2002::/16) as private when they embed internal IPv4 addresses. An authenticated attacker can subscribe to a malicious RSS feed with an enclosure URL pointing to these transition addresses. If the host environment supports NAT64 or 6to4 routing, the server will fetch and return the full response body from internal endpoints or cloud instance metadata (IMDS). The vulnerability is patched in version 9.7.1.

## Affected products

- phanan koel <= 9.7.0

## Identifiers

- CVE-2026-54494
- GHSA-rjg7-r26h-cfp2

## Timeline

- 2026-06-04: advisory: Initial advisory published on GitHub
- 2026-07-15: patched: Vulnerability fixed in version 9.7.1

## References

- [https://api.github.com/users/tonghuaroot](https://api.github.com/users/tonghuaroot)
- [https://github.com/tonghuaroot](https://github.com/tonghuaroot)
- [https://api.github.com/users/tonghuaroot/gists%7B/gist_id%7D](https://api.github.com/users/tonghuaroot/gists%7B/gist_id%7D)
- [https://api.github.com/users/tonghuaroot/repos](https://api.github.com/users/tonghuaroot/repos)
- [https://avatars.githubusercontent.com/u/23011166?v=4](https://avatars.githubusercontent.com/u/23011166?v=4)
- [https://api.github.com/users/tonghuaroot/events%7B/privacy%7D](https://api.github.com/users/tonghuaroot/events%7B/privacy%7D)

## Related threats

- [Koel SSRF in Subsonic Internet Radio Stations](https://junglewise.ai/threats/cve-2026-54493-koel-ssrf-in-subsonic-internet-radio-stations)
- [Koel authenticated blind SSRF in Subsonic podcast creation](https://junglewise.ai/threats/cve-2026-54492-koel-authenticated-blind-ssrf-in-subsonic-podcast-creation)
- [Koel SSRF in podcast and radio fetch paths](https://junglewise.ai/threats/cve-2026-54491-koel-ssrf-in-podcast-and-radio-fetch-paths)
- [Koel SSRF in Subsonic podcast feed and stream helper](https://junglewise.ai/threats/koel-ssrf-in-subsonic-podcast-feed-and-stream-helper-4a257c9c)
- [Koel SSRF in radio station creation endpoint](https://junglewise.ai/threats/cve-2026-50552-koel-ssrf-in-radio-station-creation-endpoint)