Rapid7

vulnerability

Kubernetes: CVE-2021-25735: Validating Admission Webhook does not observe some previous fields

Severity
6
CVSS
(AV:N/AC:L/Au:S/C:N/I:P/A:P)
Published
Sep 6, 2021
Added
Mar 10, 2022
Modified
Apr 17, 2026

Description

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.

Solutions

kubernetes-upgrade-1_18_18kubernetes-upgrade-1_19_10kubernetes-upgrade-1_20_6
Title
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