CVE-2020-8562

As mitigations to a report from 2019 and CVE-2020-8555, Kubernetes attempts to prevent proxied connections from accessing link-local or localhost networks when making user-driven connections to Services, Pods, Nodes, or StorageClass service providers. As part of this mitigation Kubernetes does a DNS name resolution check and validates that response IPs are not in the link-local (169.254.0.0/16) or localhost (127.0.0.0/8) range. Kubernetes then performs a second DNS resolution without validation for the actual connection. If a non-standard DNS server returns different non-cached responses, a user may be able to bypass the proxy IP restriction and access private networks on the control plane.

CVSS v3.0 3.1 LOW
CVSS v2.0 3.5 LOW

3.1^/10

CVSS v3.0 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

3.5^/10

CVSS v2.0 : LOW

Vector : AV:N/AC:M/Au:S/C:P/I:N/A:N

Exploitability : 6.8 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication SINGLE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://groups.google.com/g/kubernetes-security-announce/c/-MFX60_wdOY	Mailing List Third Party Advisory
https://github.com/kubernetes/kubernetes/issues/101493	Issue Tracking Mitigation Third Party Advisory
https://security.netapp.com/advisory/ntap-20220225-0002/	Third Party Advisory

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Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:kubernetes:kubernetes::::::::
	cpe:2.3:a:kubernetes:kubernetes::::::::
	cpe:2.3:a:kubernetes:kubernetes::::::::
	cpe:2.3:a:kubernetes:kubernetes:1.21.0:::::::*

Information

Published : 2022-02-01 03:15

Updated : 2022-03-29 09:35

NVD link : CVE-2020-8562

Mitre link : CVE-2020-8562

JSON object : View

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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Products Affected

kubernetes

kubernetes

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