CVE-2021-25735 - CVE House
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Status published Medium CVE-2021-25735

Validating Admission Webhook does not observe some previous fields

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Rogerio Bastos & Ari Lima

References

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Affected Vendor

Affected Software

Kubernetes
Vulnerable Versions:
unspecified

Timeline

Official Publish: September 6th, 2021
Last Modified: September 16th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H

Weaknesses (CWE)

CWE-372

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.