#VU53436 Information disclosure in Kubernetes - CVE-2021-25737

Vulnerability identifier: #VU53436

Vulnerability risk: Low

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

CVE-ID: CVE-2021-25737

CWE-ID: CWE-200

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 user to gain access to potentially sensitive information.

The vulnerability exists due to a host network hijacking flaw because of holes in EndpointSlice validation. A remote administrator can redirect pod traffic to private networks on a Node and gain unauthorized access to sensitive information on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Kubernetes: 1.16.0 - 1.19.10, 1.20.0 - 1.21.0

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External links
https://github.com/kubernetes/kubernetes/issues/102106
https://seclists.org/oss-sec/2021/q2/155

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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.