#VU97474 Externally Controlled Reference to a Resource in Another Sphere in Kubernetes - CVE-2020-8561

Vulnerability identifier: #VU97474

Vulnerability risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-8561

CWE-ID: CWE-610

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Kubernetes
Server applications / Frameworks for developing and running applications

Vendor: Kubernetes

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application. A remote attacker that control the responses of MutatingWebhookConfiguration or ValidatingWebhookConfiguration requests is able to redirect kube-apiserver requests to private networks of the apiserver.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Kubernetes: All versions

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External links
https://groups.google.com/g/kubernetes-security-announce/c/RV2IhwcrQsY
https://github.com/kubernetes/kubernetes/issues/104720
https://security.netapp.com/advisory/ntap-20211014-0002/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.