Vulnerability-Lookup

GHSA-XP42-V53J-R9GH

Vulnerability from github – Published: 2026-08-13 18:31 – Updated: 2026-09-05 15:30

Details

A flaw was found in the clusterclaims-controller component of Multicluster Engine (MCE). An authenticated tenant can exploit this vulnerability by manipulating ClusterClaim labels. This allows the tenant to force a cluster to join a ManagedClusterSet belonging to another tenant. Such unauthorized access could enable the injection of policies and workloads into other tenants' clusters.

Severity

7.1 (High)


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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-73266"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-441"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-13T17:17:35Z",
    "severity": "HIGH"
  },
  "details": "A flaw was found in the clusterclaims-controller component of Multicluster Engine (MCE). An authenticated tenant can exploit this vulnerability by manipulating ClusterClaim labels. This allows the tenant to force a cluster to join a ManagedClusterSet belonging to another tenant. Such unauthorized access could enable the injection of policies and workloads into other tenants\u0027 clusters.",
  "id": "GHSA-xp42-v53j-r9gh",
  "modified": "2026-09-05T15:30:25Z",
  "published": "2026-08-13T18:31:41Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-73266"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:59556"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:59557"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:59558"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:59559"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:59579"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:59593"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-73266"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2514217"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-73266 (GCVE-0-2026-73266)

Vulnerability from cvelistv5 – Published: 2026-08-13 16:36 – Updated: 2026-09-08 12:15

Title

Clusterclaims-controller: confused deputy: tenant-controlled clusterclaim labels propagated to managedcluster, enabling cross-tenant managedclusterset join

Summary

Severity

7.1 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-18 01:25 UTC

CWE

CWE-441 - Unintended Proxy or Intermediary ('Confused Deputy')

Assigner

redhat redhat root

References

8 references

URL	Tags
https://access.redhat.com/errata/RHSA-2026:59556	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:59557	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:59558	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:59559	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:59579	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:59593	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-73266	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2514217	issue-trackingx_refsource_REDHAT

Impacted products

6 products

Vendor	Product	Version
Red Hat	multicluster engine for Kubernetes 2.1	Unaffected: 1787196014 , < * (rpm) cpe:/a:redhat:multicluster_engine:2.10::el9
Red Hat	multicluster engine for Kubernetes 2.11	Unaffected: 1787239442 , < * (rpm) cpe:/a:redhat:multicluster_engine:2.11::el9
Red Hat	multicluster engine for Kubernetes 2.17	Unaffected: 1786577950 , < * (rpm) cpe:/a:redhat:multicluster_engine:2.17::el9
Red Hat	multicluster engine for Kubernetes 2.6	Unaffected: 1787259112 , < * (rpm) cpe:/a:redhat:multicluster_engine:2.6::el9
Red Hat	multicluster engine for Kubernetes 2.8	Unaffected: 1787259059 , < * (rpm) cpe:/a:redhat:multicluster_engine:2.8::el9
Red Hat	multicluster engine for Kubernetes 2.9	Unaffected: 1787195995 , < * (rpm) cpe:/a:redhat:multicluster_engine:2.9::el9

Date Public

2026-08-11 00:00

Show details on NVD website

JSON

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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.

Detection rules are retrieved from Rulezet.

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.