CVE-2021-25735

A security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission Webhook for Nodes that denies admission based at least partially on the old state of the Node object. Validating Admission Webhook does not observe some previous fields.

CVSS v3.0 6.5 MEDIUM
CVSS v2.0 5.5 MEDIUM

6.5^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

5.5^/10

CVSS v2.0 : MEDIUM

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

Exploitability : 8.0 / Impact : 4.9

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://groups.google.com/g/kubernetes-security-announce/c/FKAGqT4jx9Y	Mailing List Third Party Advisory
https://github.com/kubernetes/kubernetes/issues/100096	Patch 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::::::::

Information

Published : 2021-09-06 05:15

Updated : 2021-09-13 10:12

NVD link : CVE-2021-25735

Mitre link : CVE-2021-25735

JSON object : View

CWE

CWE-863

Incorrect Authorization

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Products Affected

kubernetes

kubernetes

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