CVE-2026-54589
Deferred
Deferred - Pending Action
Chartbrew Outbound URL Bypass via NAT64 IPv4 Embedding
Vulnerability report for CVE-2026-54589, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-06
Last updated on: 2026-11-06
Assigner: GitHub, Inc.
Description
Description
Chartbrew is an open-source web application that can connect directly to databases and APIs and use the data to create charts. Prior to 5.2.1, the outbound URL guard recognized ordinary IPv4, IPv6, and IPv4-mapped IPv6 destinations but did not recognize IPv4 addresses embedded in NAT64 prefixes. The vulnerable surface is aPI Data Connection outbound requests routed through server/modules/outboundTargetPolicy.js. An authenticated user with permission to create or edit an API connection supplies an attacker-controlled hostname or redirect whose DNS answer is a NAT64 address embedding a private or link-local IPv4 destination. The policy treated the NAT64 address as public; a NAT64 gateway then translated it to the embedded private IPv4 address after validation. The bypass requires a NAT64/DNS64 deployment path and connection-management privileges. IPv4-only deployments are not affected by this specific bypass. The attacker can read responses from 169.254.169.254 cloud metadata and arbitrary internal IPv4 hosts and ports reachable through the NAT64 gateway. This issue is fixed in version 5.2.1.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-918 | The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. |