Kube-proxy up to 1.20.5 on Windows status.loadBalancer.ingress[].ip access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Kube-proxy up to 1.20.5 on Windows. Affected by this vulnerability is an unknown functionality. Executing a manipulation of the argument status.loadBalancer.ingress[].ip can lead to access control. This vulnerability is handled as CVE-2021-25736. The attack can be executed remotely. There is not any exploit available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in Kube-proxy up to 1.20.5 on Windows (Firewall Software). It has been declared as problematic. This vulnerability affects some unknown functionality. The manipulation of the argument status.loadBalancer.ingress[].ip with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. As an impact it is known to affect confidentiality. CVE summarizes:

Kube-proxy on Windows can unintentionally forward traffic to local processes listening on the same port (“spec.ports[*].port”) as a LoadBalancer Service when the LoadBalancer controller does not set the “status.loadBalancer.ingress[].ip” field. Clusters where the LoadBalancer controller sets the “status.loadBalancer.ingress[].ip” field are unaffected.

The weakness was released 10/30/2023 by Eric Paris. The advisory is available at github.com. This vulnerability was named CVE-2021-25736 since 01/21/2021. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 2.2
VulDB Temp Score: 2.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.3
NVD Vector: 🔍

CNA Base Score: 5.8
CNA Vector (Kubernetes): 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: github.com

Timelineinfo

01/21/2021 🔍
10/30/2023 +1012 days 🔍
10/30/2023 +0 days 🔍
06/12/2025 +591 days 🔍

Sourcesinfo

Advisory: github.com
Researcher: Eric Paris
Status: Confirmed

CVE: CVE-2021-25736 (🔍)
GCVE (CVE): GCVE-0-2021-25736
GCVE (VulDB): GCVE-100-243826

Entryinfo

Created: 10/30/2023 07:27
Updated: 06/12/2025 19:09
Changes: 10/30/2023 07:27 (53), 11/19/2023 18:48 (11), 06/12/2025 19:09 (16)
Complete: 🔍
Cache ID: 216::103

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