# CVE-2026-86777: AlchemyCMS authentication bypass in /api/nodes endpoint

Source: https://junglewise.ai/threats/cve-2026-86777-alchemycms-authentication-bypass-in-api-nodes-endpoint  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-09. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-86777 · Severity: medium · CVSS 5.3 · Published 2026-09-09

AlchemyCMS is an open-source Rails content management system used to build websites. A flaw in versions before 7.4.16 and 8.x before 8.3.6 allows attackers to access the /api/nodes endpoint without authentication, exposing the internal structure of all sites—including hidden page names, URL paths, and internal links across multiple languages. This disclosure of site structure can facilitate further attacks and reveal sensitive organizational information.

## Quick answers

**Is CVE-2026-86777 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-86777 being exploited in the wild.

**How severe is CVE-2026-86777?** Medium severity, with a CVSS score of 5.3, published 9 September 2026.

**Which products and versions are affected?** AlchemyCMS Alchemy CMS 7.x before 7.4.16, 8.x before 8.3.6.

**Is there a fix for CVE-2026-86777?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-86777 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-86777?** Check whether anything you run is named in the advisory. 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.

## Technical details

The vulnerability is an authentication bypass in the GET /api/nodes API endpoint that fails to enforce proper authorization checks. Attackers can send unauthenticated requests to retrieve navigation node data, which includes restricted page metadata such as page names, URL paths, and internal references from all configured sites and languages. The attack requires only network access to the vulnerable endpoint; no credentials or user interaction is needed. The vulnerability affects AlchemyCMS versions 7.x before 7.4.16 and all 8.x versions before 8.3.6. Patches are available in versions 7.4.16 and 8.3.6 or later.

## Affected products

- AlchemyCMS Alchemy CMS 7.x before 7.4.16, 8.x before 8.3.6

## Timeline

- 2026-09-09: disclosed

## References

- [https://rubygems.org/gems/alchemy_cms](https://rubygems.org/gems/alchemy_cms)
- [https://github.com/AlchemyCMS/alchemy_cms](https://github.com/AlchemyCMS/alchemy_cms)