Vulnerability-Lookup

CVE-2026-66795 (GCVE-0-2026-66795)

Vulnerability from cvelistv5 – Published: 2026-08-17 20:45 – Updated: 2026-08-18 15:15

Title

Managedcluster-import-controller: managedcluster-import-controller: csr auto-approver does not validate certificate subject, signername, or requester identity

Summary

A flaw was found in the managedcluster-import-controller. The Certificate Signing Request (CSR) auto-approval logic improperly validates incoming CSRs, specifically by not inspecting the signer name or decoding the PEM-encoded x509 CSR. This vulnerability allows a privileged service account on a spoke cluster to submit a malicious CSR. Successful exploitation can lead to privilege escalation, enabling the attacker to obtain administrative credentials on the hub cluster.

Severity

9.1 (Critical)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-18 15:15 UTC

CWE

CWE-295 - Improper Certificate Validation

Assigner

redhat redhat root

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-66795	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2507540	issue-trackingx_refsource_REDHAT

Impacted products

1 product

Vendor	Product	Version	CPE status
Red Hat	Multicluster Engine for Kubernetes	cpe:/a:redhat:multicluster_engine

Date Public

2026-08-17 20:29

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-66795

Vulnerability from fkie_nvd - Published: 2026-08-17 21:16 - Updated: 2026-08-18 15:04

Severity

9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Summary

References

	URL	Tags
	secalert@redhat.com	https://access.redhat.com/security/cve/CVE-2026-66795
	secalert@redhat.com	https://bugzilla.redhat.com/show_bug.cgi?id=2507540

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:multicluster_engine"
          ],
          "defaultStatus": "affected",
          "packageName": "multicluster-engine/managedcluster-import-controller-rhel9",
          "product": "Multicluster Engine for Kubernetes",
          "vendor": "Red Hat"
        }
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      "source": "secalert@redhat.com"
    }
  ],
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    }
  ],
  "id": "CVE-2026-66795",
  "lastModified": "2026-08-18T15:04:46.610",
  "metrics": {
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        },
        "exploitabilityScore": 2.3,
        "impactScore": 6.0,
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        "type": "Primary"
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  "published": "2026-08-17T21:16:47.163",
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}

GHSA-W9C6-W29V-4VP6

Vulnerability from github – Published: 2026-08-17 21:31 – Updated: 2026-08-17 21:31

Details

Severity

9.1 (Critical)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-66795"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
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    "severity": "CRITICAL"
  },
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  "id": "GHSA-w9c6-w29v-4vp6",
  "modified": "2026-08-17T21:31:25Z",
  "published": "2026-08-17T21:31:25Z",
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    {
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-66795"
    },
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    {
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      "type": "CVSS_V3"
    }
  ]
}

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.

Action not permitted

CVE-2026-66795 (GCVE-0-2026-66795)

FKIE_CVE-2026-66795

GHSA-W9C6-W29V-4VP6

Tags

Sightings

Nomenclature