CVE-2021-25735— Validating Admission Webhook does not observe some previous fields
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I. Basic Information for CVE-2021-25735
Vulnerability Information
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Vulnerability Title
Validating Admission Webhook does not observe some previous fields
Source: NVD (National Vulnerability Database)
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.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H
Source: NVD (National Vulnerability Database)
Vulnerability Type
不完整的内部状态区分
Source: NVD (National Vulnerability Database)
Vulnerability Title
Kubernetes SIGs kube-apiserver 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Kubernetes SIGs kube-apiserver是Kubernetes SIGs开源的一个应用软件。验证并配置api对象的数据，这些对象包括容器，服务，复制控制器等。 Kubernetes SIGs kube-apiserver 存在安全漏洞，该漏洞允许节点更新绕过一个验证接纳的Webhook。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Kubernetes | Kubernetes | unspecified ~ 1.18.17 | - |
II. Public POCs for CVE-2021-25735
| # | POC Description | Source Link | Shenlong Link |
|---|---|---|---|
| 1 | Exploit CVE-2021-25735: Kubernetes Validating Admission Webhook Bypass | https://github.com/darryk10/CVE-2021-25735 | POC Details |
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- https://github.com/kubernetes/kubernetes/issues/100096x_refsource_MISC
- https://nvd.nist.gov/vuln/detail/CVE-2021-25735
IV. Related Vulnerabilities
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Same weakness: CWE-372
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V. Comments for CVE-2021-25735
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