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.
Problem types
CWE-754 Improper Check for Unusual or Exceptional Conditions
Product status
Any version before 1.13.7
Any version before 1.14.3
Credits
Aurelia Schittler
References
github.com/kubernetes/kubernetes/issues/136679