The Kubernetes ingress-nginx component prior to version 0.28.0 allows a user with the ability to create namespaces and to read and create ingress objects to overwrite the password file of another ingress which uses nginx.ingress.kubernetes.io/auth-type: basic and which has a hyphenated namespace or secret name.
A security issue was discovered in ingress-nginx versions older than v0.28.0. The issue is of medium severity, and upgrading is encouraged to fix the vulnerability.

**Am I vulnerable?**

The vulnerability exists only if the annotation [nginx.ingress.kubernetes.io/auth-type: basic](https://kubernetes.github.io/ingress-nginx/user-guide/nginx-configuration/annotations/#authentication) is used.

**How do I upgrade?**

Follow installation instructions [here](https://kubernetes.github.io/ingress-nginx/deploy/upgrade/)

**Vulnerability Details**

A vulnerability has been discovered where a malicious user could create a new Ingress definition resulting in the replacement of the password file. The vulnerability requires that the victim namespace and/or secret use a hyphen in the name.

This scenario requires privileges in the cluster to create and read ingresses and also create secrets.

This issue is filed as CVE-2020-8553.

/close

CVE-2020-8553: auth-type basic annotation vulnerability
This is a GitHub Issue
repo:ingress-nginx
owner:kubernetes
Title : CVE-2020-8553: auth-type basic annotation vulnerability
Issue date:

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A security issue was discovered in ingress-nginx versions older than v0.28.0. The issue is of medium severity, and upgrading is encouraged to fix the vulnerability.

**Am I vulnerable?**

The vulnerability exists only if the annotation [nginx.ingress.kubernetes.io/auth-type: basic](https://kubernetes.github.io/ingress-nginx/user-guide/nginx-configuration/annotations/#authentication) is used.

**How do I upgrade?**

Follow installation instructions [here](https://kubernetes.github.io/ingress-nginx/deploy/upgrade/)

**Vulnerability Details**

A vulnerability has been discovered where a malicious user could create a new Ingress definition resulting in the replacement of the password file. The vulnerability requires that the victim namespace and/or secret use a hyphen in the name.

This scenario requires privileges in the cluster to create and read ingresses and also create secrets.

This issue is filed as CVE-2020-8553.

/close

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A security vulnerability (CVE-2020-8553) in ingress-nginx versions older than v0.28.0 allows a malicious user to replace the password file by creating a new Ingress definition, provided that the victim namespace and/or secret contains a hyphen in the name. This requires privileges to create and read ingresses and secrets.