MSRC_CVE-2026-27211

Vulnerability from csaf_microsoft - Published: 2026-02-02 00:00 - Updated: 2026-02-26 14:36
Summary
Cloud Hypervisor: Host File Exfiltration via QCOW Backing File Abuse

Notes

Additional Resources
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer
The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
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{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-27211 Cloud Hypervisor: Host File Exfiltration via QCOW Backing File Abuse - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-27211.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "Cloud Hypervisor: Host File Exfiltration via QCOW Backing File Abuse",
    "tracking": {
      "current_release_date": "2026-02-26T14:36:00.000Z",
      "generator": {
        "date": "2026-02-27T08:14:38.533Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
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      "id": "msrc_CVE-2026-27211",
      "initial_release_date": "2026-02-02T00:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-02-25T01:03:39.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
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  },
  "product_tree": {
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      {
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            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              },
              {
                "category": "product_version",
                "name": "2.0",
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                }
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            ],
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            "name": "Azure Linux"
          },
          {
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              {
                "category": "product_version_range",
                "name": "\u003cazl3 cloud-hypervisor 48.0.246-1",
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                }
              }
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      }
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    "relationships": [
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        "category": "default_component_of",
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        "relates_to_product_reference": "17084"
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        "relates_to_product_reference": "17084"
      },
      {
        "category": "default_component_of",
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          "product_id": "17086-2"
        },
        "product_reference": "2",
        "relates_to_product_reference": "17086"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-27211",
      "cwe": {
        "id": "CWE-73",
        "name": "External Control of File Name or Path"
      },
      "notes": [
        {
          "category": "general",
          "text": "GitHub_M",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "fixed": [
          "20926-17084"
        ],
        "known_affected": [
          "17084-1",
          "17086-2"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-27211 Cloud Hypervisor: Host File Exfiltration via QCOW Backing File Abuse - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-27211.json"
        }
      ],
      "remediations": [
        {
          "category": "none_available",
          "date": "2026-02-25T01:03:39.000Z",
          "details": "There is no fix available for this vulnerability as of now",
          "product_ids": [
            "17086-2"
          ]
        },
        {
          "category": "vendor_fix",
          "date": "2026-02-25T01:03:39.000Z",
          "details": "48.0.246-2:Security Update:https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade",
          "product_ids": [
            "17084-1"
          ],
          "url": "https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 10.0,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "environmentalsScore": 0.0,
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "temporalScore": 10.0,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N",
            "version": "3.1"
          },
          "products": [
            "17084-1",
            "17086-2"
          ]
        }
      ],
      "title": "Cloud Hypervisor: Host File Exfiltration via QCOW Backing File Abuse"
    }
  ]
}


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Sightings

Author Source Type Date

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.