A security issue was discovered in ingress-nginx where the protection afforded by the `auth-url` Ingress annotation may not be effective in the presence of a specific misconfiguration.

If the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the `auth-url` annotation may be accessed even when authentication fails.

Note that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-4g2f-xcph-2335 ingress-nginx has Improper Check for Unusual or Exceptional Conditions
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 04 Feb 2026 19:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 04 Feb 2026 12:15:00 +0000

Type Values Removed Values Added
First Time appeared Kubernetes
Kubernetes ingress-nginx
Vendors & Products Kubernetes
Kubernetes ingress-nginx

Tue, 03 Feb 2026 22:45:00 +0000

Type Values Removed Values Added
Description A security issue was discovered in ingress-nginx where the protection afforded by the `auth-url` Ingress annotation may not be effective in the presence of a specific misconfiguration. If the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the `auth-url` annotation may be accessed even when authentication fails. Note that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component.
Title ingress-nginx auth-url protection bypass
Weaknesses CWE-754
References
Metrics cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: kubernetes

Published:

Updated: 2026-02-06T03:14:53.353Z

Reserved: 2026-01-23T06:54:35.913Z

Link: CVE-2026-24513

cve-icon Vulnrichment

Updated: 2026-02-04T18:20:54.231Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-02-03T23:16:07.130

Modified: 2026-02-04T16:33:44.537

Link: CVE-2026-24513

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-02-04T12:05:46Z

Weaknesses