aad-pod-identity assigns Azure Active Directory identities to Kubernetes applications and has now been deprecated as of 24 October 2022. The NMI component in AAD Pod Identity intercepts and validates token requests based on regex. In this case, a token request made with backslash in the request (example: `/metadata/identity\oauth2\token/`) would bypass the NMI validation and be sent to IMDS allowing a pod in the cluster to access identities that it shouldn't have access to. This issue has been fixed and has been included in AAD Pod Identity release version 1.8.13. If using the AKS pod-managed identities add-on, no action is required. The clusters should now be running the version 1.8.13 release.

Affected: Go: github.com/Azure/aad-pod-identity

### Impact _What kind of vulnerability is it? Who is impacted?_ The [NMI](https://azure.github.io/aad-pod-identity/docs/concepts/nmi/) component in AAD Pod Identity intercepts and validates token requests based on regex. In this case, a token request made with backslash in the request (example: `/metadata/identity\oauth2\token/`) would bypass the NMI validation and be sent to [IMDS](https://learn.microsoft.com/en-us/azure/virtual-machines/windows/instance-metadata-service?tabs=windows) allowing a pod in the cluster to access identities that it shouldn't have access to.

### Patches _Has the problem been patched? What versions should users upgrade to?_ - We analyzed this bug and determined that we needed to fix it. This fix has been included in AAD Pod Identity release [v1.8.13](https://github.com/Azure/aad-pod-identity/releases/tag/v1.8.13) - If using the [AKS pod-managed identities add-on](https://learn.microsoft.com/en-us/azure/aks/use-azure-ad-pod-identity), no action is required. The clusters should now be running the `v1.8.13` release.

### For more information

If you have any questions or comments about this advisory:

Open an issue in [Azure/aad-pod-identity](https://github.com/Azure/aad-pod-identity)