Vulnerability-Lookup

RHSA-2021_2130

Vulnerability from csaf_redhat - Published: 2021-06-23 05:37 - Updated: 2024-11-22 17:00

Summary

Red Hat Security Advisory: Windows Container Support for Red Hat OpenShift 2.0.1 security and bug fix update

Severity

Moderate

Notes

Topic: The components for Windows Container Support for Red Hat OpenShift 2.0.1 are now available. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Details: Windows Container Support for Red Hat OpenShift allows you to deploy Windows container workloads running on Windows Server containers. Security Fix(es): * kubernetes: LoadBalancer Service type don't create a HNS policy for empty or invalid external loadbalancer IP, what could lead to MITM (CVE-2021-25736) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Bug Fix(es): * WMCO patch pub-key-hash annotation to Linux node (BZ#1945248) * LoadBalancer Service type with invalid external loadbalancer IP breaks the datapath (BZ#1952917) * Telemetry info not completely available to identify windows nodes (BZ#1955319) * WMCO incorrectly shows node as ready after a failed configuration (BZ#1956412) * kube-proxy service terminated unexpectedly after recreated LB service (BZ#1963263)

Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.

CVE-2021-25736

A flaw was found in the Windows kube-proxy component. In a cloud environment that does not set the “.status.loadBalancer.ingress.ip” field in the LoadBalancer service status configuration (for example in AWS) the packets can be misrouted and reach an unintended destination.

5.8 (Medium)


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

CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor

Affected products

Fixed 2 products

Product	Identifier	Version	Remediation
Unresolved product id: 8Base-RHOSE-4.7:openshift4-wincw/windows-machine-config-operator-bundle@sha256:60ab0ad722725d13abdede0fa569ee4ad2ec95350584dfd51c016510142f0523_amd64		—	Vendor Fix fix
Unresolved product id: 8Base-RHOSE-4.7:openshift4-wincw/windows-machine-config-rhel8-operator@sha256:34a7784ef1e4cd3aa4a8c2151006ef56a60c8b30c9a7e25cdb198036de8c27e9_amd64		—	Vendor Fix fix

Threats

Impact Moderate

References

15 references

URL	Category
https://access.redhat.com/errata/RHSA-2021:2130	self
https://access.redhat.com/security/updates/classi…	external
https://bugzilla.redhat.com/show_bug.cgi?id=1945248	external
https://bugzilla.redhat.com/show_bug.cgi?id=1946538	external
https://bugzilla.redhat.com/show_bug.cgi?id=1952917	external
https://bugzilla.redhat.com/show_bug.cgi?id=1955319	external
https://bugzilla.redhat.com/show_bug.cgi?id=1956412	external
https://bugzilla.redhat.com/show_bug.cgi?id=1963263	external
https://issues.redhat.com/browse/WINC-623	external
https://security.access.redhat.com/data/csaf/v2/a…	self
https://access.redhat.com/security/cve/CVE-2021-25736	self
https://bugzilla.redhat.com/show_bug.cgi?id=1946538	external
https://www.cve.org/CVERecord?id=CVE-2021-25736	external
https://nvd.nist.gov/vuln/detail/CVE-2021-25736	external
https://groups.google.com/g/kubernetes-security-a…	external

Acknowledgments

Red Hat Eric Paris Christian Hernandez

JSON

To clipboard

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            "integrityImpact": "NONE",
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            "scope": "CHANGED",
            "userInteraction": "NONE",
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  ]
}

CVE-2021-25736 (GCVE-0-2021-25736)

Vulnerability from cvelistv5 – Published: 2023-10-30 02:19 – Updated: 2025-06-12 14:42

Title

Windows kube-proxy LoadBalancer contention

Summary

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.

Severity

5.8 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-06-12 14:39 UTC

CWE

CWE-114 - Process Control

Assigner

kubernetes CNA under the mitre root

CNA scorecard – unranked: 2 records in the last 180 days, 10 needed details

References

3 references

URL	Tags
https://github.com/kubernetes/kubernetes/pull/99958
https://groups.google.com/g/kubernetes-security-a…
https://security.netapp.com/advisory/ntap-2023122…

Impacted products

1 product

Vendor	Product	Version
Kubernetes	Kubernetes	Affected: 0 , ≤ v1.20.5 (v1.20.5)

Credits

Eric Paris Christian Hernandez

Show details on NVD website

JSON

To clipboard

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        }
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          "cvssV3_1": {
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    "dateReserved": "2021-01-21T21:42:58.237Z",
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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