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.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
- Attack Vector
- network
- Complexity
- high
- Privileges
- low
- User Action
- none
- Scope
- unchanged
- Confidentiality
- low
- Integrity
- none
- Availability
- none
- Weaknesses
- CWE-754
Metadata
- Primary Vendor
- UNKNOWN
- Published
- 2/3/2026
- Last Modified
- 2/4/2026
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
No affected products information available.
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