{ "document": { "category": "csaf_base", "csaf_version": "2.0", "distribution": { "tlp": { "label": "WHITE" } }, "lang": "en", "notes": [ { "category": "legal_disclaimer", "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings." } ], "publisher": { "category": "coordinator", "contact_details": "cert@ncsc.nl", "name": "National Cyber Security Centre", "namespace": "https://www.ncsc.nl/" }, "title": "CVE-2026-27211", "tracking": { "current_release_date": "2026-03-20T09:42:04.384147Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-27211", "initial_release_date": "2026-02-21T06:25:02.005594Z", "revision_history": [ { "date": "2026-02-21T06:25:02.005594Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (7).| CWES updated (1)." }, { "date": "2026-02-21T06:25:11.097407Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-02-21T06:38:41.803140Z", "number": "3", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (1).| References created (7).| CWES updated (1)." }, { "date": "2026-02-21T06:38:50.119431Z", "number": "4", "summary": "NCSC Score updated." }, { "date": "2026-02-21T11:35:01.132276Z", "number": "5", "summary": "NCSC Score updated." }, { "date": "2026-02-21T14:14:42.179039Z", "number": "6", "summary": "Source created.| CVE status created. (valid)| EPSS created." }, { "date": "2026-02-21T14:14:43.804120Z", "number": "7", "summary": "NCSC Score updated." }, { "date": "2026-02-22T00:22:16.081701Z", "number": "8", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (17).| References created (9).| CWES updated (1)." }, { "date": "2026-02-22T00:22:18.572702Z", "number": "9", "summary": "NCSC Score updated." }, { "date": "2026-02-24T17:25:10.738786Z", "number": "10", "summary": "CVSS created.| Products created (1).| Product Identifiers created (1)." }, { "date": "2026-02-24T17:25:13.097448Z", "number": "11", "summary": "NCSC Score updated." }, { "date": "2026-02-25T12:20:17.809265Z", "number": "12", "summary": "Source connected.| CVE status created. (valid)| Description created for source.| CVSS created.| CWES updated (1)." }, { "date": "2026-02-25T21:38:48.370325Z", "number": "13", "summary": "Unknown change." }, { "date": "2026-02-27T00:19:36.393900Z", "number": "14", "summary": "Products created (2).| Product Identifiers created (2)." }, { "date": "2026-02-27T00:19:38.682394Z", "number": "15", "summary": "NCSC Score updated." }, { "date": "2026-02-27T12:19:42.891597Z", "number": "16", "summary": "Product Remediations created (1)." }, { "date": "2026-02-27T12:19:53.684702Z", "number": "17", "summary": "NCSC Score updated." }, { "date": "2026-02-28T00:19:32.521408Z", "number": "18", "summary": "Product Remediations removed (1)." }, { "date": "2026-02-28T00:19:36.258153Z", "number": "19", "summary": "NCSC Score updated." }, { "date": "2026-02-28T12:20:17.355239Z", "number": "20", "summary": "Product Remediations created (1)." }, { "date": "2026-02-28T12:20:19.684657Z", "number": "21", "summary": "NCSC Score updated." }, { "date": "2026-03-20T09:41:59.744969Z", "number": "22", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-03-20T09:42:03.069633Z", "number": "23", "summary": "NCSC Score updated." } ], "status": "interim", "version": "23" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/>=34.0|<50.1", "product": { "name": "vers:unknown/>=34.0|<50.1", "product_id": "CSAFPID-5657225" } }, { "category": "product_version_range", "name": "vers:unknown/v34.0", "product": { "name": "vers:unknown/v34.0", "product_id": "CSAFPID-5661596" } }, { "category": "product_version_range", "name": "vers:unknown/v35.0", "product": { "name": "vers:unknown/v35.0", "product_id": "CSAFPID-5661597" } }, { "category": "product_version_range", "name": "vers:unknown/v36.0", "product": { "name": "vers:unknown/v36.0", "product_id": "CSAFPID-5661598" } }, { "category": "product_version_range", "name": "vers:unknown/v37.0", "product": { "name": "vers:unknown/v37.0", "product_id": "CSAFPID-5661599" } }, { "category": "product_version_range", "name": "vers:unknown/v38.0", "product": { "name": "vers:unknown/v38.0", "product_id": "CSAFPID-5661600" } }, { "category": "product_version_range", "name": "vers:unknown/v39.0", "product": { "name": "vers:unknown/v39.0", "product_id": "CSAFPID-5661601" } }, { "category": "product_version_range", "name": "vers:unknown/v40.0", "product": { "name": "vers:unknown/v40.0", "product_id": "CSAFPID-5661602" } }, { "category": "product_version_range", "name": "vers:unknown/v41.0", "product": { "name": "vers:unknown/v41.0", "product_id": "CSAFPID-5661603" } }, { "category": "product_version_range", "name": "vers:unknown/v42.0", "product": { "name": "vers:unknown/v42.0", "product_id": "CSAFPID-5661604" } }, { "category": "product_version_range", "name": "vers:unknown/v43.0", "product": { "name": "vers:unknown/v43.0", "product_id": "CSAFPID-5661605" } }, { "category": "product_version_range", "name": "vers:unknown/v44.0", "product": { "name": "vers:unknown/v44.0", "product_id": "CSAFPID-5661606" } }, { "category": "product_version_range", "name": "vers:unknown/v45.0", "product": { "name": "vers:unknown/v45.0", "product_id": "CSAFPID-5661607" } }, { "category": "product_version_range", "name": "vers:unknown/v46.0", "product": { "name": "vers:unknown/v46.0", "product_id": "CSAFPID-5661608" } }, { "category": "product_version_range", "name": "vers:unknown/v47.0", "product": { "name": "vers:unknown/v47.0", "product_id": "CSAFPID-5661609" } }, { "category": "product_version_range", "name": "vers:unknown/v48.0", "product": { "name": "vers:unknown/v48.0", "product_id": "CSAFPID-5661610" } }, { "category": "product_version_range", "name": "vers:unknown/v49.0", "product": { "name": "vers:unknown/v49.0", "product_id": "CSAFPID-5661611" } }, { "category": "product_version_range", "name": "vers:unknown/v50.0", "product": { "name": "vers:unknown/v50.0", "product_id": "CSAFPID-5661612" } } ], "category": "product_name", "name": "Cloud Hypervisor" } ], "category": "vendor", "name": "Cloudhypervisor" }, { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:microsoft/*", "product": { "name": "vers:microsoft/*", "product_id": "CSAFPID-5733332", "product_identification_helper": { "cpe": "cpe:2.3:a:microsoft:azl3_cloud-hypervisor_48.0.246-1:*:*:*:*:*:*:*:*" } } } ], "category": "product_name", "name": "azl3 cloud-hypervisor 48.0.246-1 on Azure Linux 3.0" }, { "branches": [ { "category": "product_version_range", "name": "vers:microsoft/*", "product": { "name": "vers:microsoft/*", "product_id": "CSAFPID-5733333", "product_identification_helper": { "cpe": "cpe:2.3:a:microsoft:cbl2_cloud-hypervisor-cvm_38.0.72.2-5:*:*:*:*:*:*:*:*" } } } ], "category": "product_name", "name": "cbl2 cloud-hypervisor-cvm 38.0.72.2-5 on CBL Mariner 2.0" } ], "category": "product_family", "name": "Open Source Software" } ], "category": "vendor", "name": "Microsoft" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/>=34.0|<50.1", "product": { "name": "vers:unknown/>=34.0|<50.1", "product_id": "CSAFPID-5691945", "product_identification_helper": { "cpe": "cpe:2.3:a:cloudhypervisor:cloud_hypervisor:*:*:*:*:*:rust:*:*" } } } ], "category": "product_name", "name": "cloud_hypervisor" } ], "category": "vendor", "name": "cloudhypervisor" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-27211", "cwe": { "id": "CWE-73", "name": "External Control of File Name or Path" }, "notes": [ { "category": "description", "text": "Cloud Hypervisor is a Virtual Machine Monitor for Cloud workloads. Versions 34.0 through 50.0 arevulnerable to arbitrary host file exfiltration (constrained by process privileges) when using virtio-block devices backed by raw images. A malicious guest can overwrite its disk header with a crafted QCOW2 structure pointing to a sensitive host path. Upon the next VM boot or disk scan, the image format auto-detection parses this header and serves the host file's contents to the guest. Guest-initiated VM reboots are sufficient to trigger a disk scan and do not cause the Cloud Hypervisor process to exit. Therefore, a single VM can perform this attack without needing interaction from the management stack. Successful exploitation requires the backing image to be either writable by the guest or sourced from an untrusted origin. Deployments utilizing only trusted, read-only images are not affected. This issue has been fixed in version 50.1. To workaround, enable land lock sandboxing and restrict process privileges and access.", "title": "nvd - https://nvd.nist.gov/vuln/detail/CVE-2026-27211" }, { "category": "description", "text": "Cloud Hypervisor is a Virtual Machine Monitor for Cloud workloads. Versions 34.0 through 50.0 arevulnerable to arbitrary host file exfiltration (constrained by process privileges) when using virtio-block devices backed by raw images. A malicious guest can overwrite its disk header with a crafted QCOW2 structure pointing to a sensitive host path. Upon the next VM boot or disk scan, the image format auto-detection parses this header and serves the host file's contents to the guest. Guest-initiated VM reboots are sufficient to trigger a disk scan and do not cause the Cloud Hypervisor process to exit. Therefore, a single VM can perform this attack without needing interaction from the management stack. Successful exploitation requires the backing image to be either writable by the guest or sourced from an untrusted origin. Deployments utilizing only trusted, read-only images are not affected. This issue has been fixed in version 50.1. To workaround, enable land lock sandboxing and restrict process privileges and access.", "title": "cveprojectv5 - https://www.cve.org/CVERecord?id=CVE-2026-27211" }, { "category": "description", "text": "Cloud Hypervisor is a Virtual Machine Monitor for Cloud workloads. Versions 34.0 through 50.0 arevulnerable to arbitrary host file exfiltration (constrained by process privileges) when using virtio-block devices backed by raw images. A malicious guest can overwrite its disk header with a crafted QCOW2 structure pointing to a sensitive host path. Upon the next VM boot or disk scan, the image format auto-detection parses this header and serves the host file's contents to the guest. Guest-initiated VM reboots are sufficient to trigger a disk scan and do not cause the Cloud Hypervisor process to exit. Therefore, a single VM can perform this attack without needing interaction from the management stack. Successful exploitation requires the backing image to be either writable by the guest or sourced from an untrusted origin. Deployments utilizing only trusted, read-only images are not affected. This issue has been fixed in version 50.1. To workaround, enable land lock sandboxing and restrict process privileges and access.", "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-27211.json?alt=media" }, { "category": "description", "text": "Cloud Hypervisor: Host File Exfiltration via QCOW Backing File Abuse", "title": "microsoft - https://api.msrc.microsoft.com/cvrf/v3.0/cvrf/2026-Feb" }, { "category": "other", "text": "0.00048", "title": "EPSS" }, { "category": "other", "text": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "title": "CVSSV4" }, { "category": "other", "text": "9.1", "title": "CVSSV4 base score" }, { "category": "other", "text": "4.7", "title": "NCSC Score" }, { "category": "other", "text": "VENDOR FIX as product remediation category", "title": "NCSC Score top increasing factors" }, { "category": "other", "text": "Is related to (a version of) an uncommon product, Is related to an uncommon product vendor", "title": "NCSC Score top decreasing factors" } ], "product_status": { "known_affected": [ "CSAFPID-5657225", "CSAFPID-5661596", "CSAFPID-5661597", "CSAFPID-5661598", "CSAFPID-5661599", "CSAFPID-5661600", "CSAFPID-5661601", "CSAFPID-5661602", "CSAFPID-5661603", "CSAFPID-5661604", "CSAFPID-5661605", "CSAFPID-5661606", "CSAFPID-5661607", "CSAFPID-5661608", "CSAFPID-5661609", "CSAFPID-5661610", "CSAFPID-5661611", "CSAFPID-5661612", "CSAFPID-5691945", "CSAFPID-5733332", "CSAFPID-5733333" ] }, "references": [ { "category": "external", "summary": "Source - nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-27211" }, { "category": "external", "summary": "Source raw - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-27211" }, { "category": "external", "summary": "Source - cveprojectv5", "url": "https://www.cve.org/CVERecord?id=CVE-2026-27211" }, { "category": "external", "summary": "Source raw - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/27xxx/CVE-2026-27211.json" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-27211" }, { "category": "external", "summary": "Source raw - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0" }, { "category": "external", "summary": "Source - osv", "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-27211.json?alt=media" }, { "category": "external", "summary": "Source - microsoft", "url": "https://api.msrc.microsoft.com/cvrf/v3.0/cvrf/2026-Feb" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/cloud-hypervisor/cloud-hypervisor/commit/081a6ebb5184228ff348601502258f3f72bd8b43" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/cloud-hypervisor/cloud-hypervisor/commit/509832298b6865365b00bda88722e76e41ce7f41" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/cloud-hypervisor/cloud-hypervisor/commit/a63315df54e06f6ec867f17b63076c266e2d8648" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/cloud-hypervisor/cloud-hypervisor/commit/cb495959a8bea1b56e8fc82d15ba527a0e7fcf3c" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/cloud-hypervisor/cloud-hypervisor/releases/tag/v50.1" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/cloud-hypervisor/cloud-hypervisor/releases/tag/v51.0" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd; osv", "url": "https://github.com/cloud-hypervisor/cloud-hypervisor/security/advisories/GHSA-jmr4-g2hv-mjj6" }, { "category": "external", "summary": "Reference - osv", "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27211.json" }, { "category": "external", "summary": "Reference - osv", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-27211" } ], "remediations": [ { "category": "vendor_fix", "details": "CBL-Mariner Releases", "product_ids": [ "CSAFPID-5733332" ] } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N", "baseScore": 10.0, "baseSeverity": "CRITICAL" }, "products": [ "CSAFPID-5657225", "CSAFPID-5661596", "CSAFPID-5661597", "CSAFPID-5661598", "CSAFPID-5661599", "CSAFPID-5661600", "CSAFPID-5661601", "CSAFPID-5661602", "CSAFPID-5661603", "CSAFPID-5661604", "CSAFPID-5661605", "CSAFPID-5661606", "CSAFPID-5661607", "CSAFPID-5661608", "CSAFPID-5661609", "CSAFPID-5661610", "CSAFPID-5661611", "CSAFPID-5661612", "CSAFPID-5691945", "CSAFPID-5733332", "CSAFPID-5733333" ] } ], "title": "CVE-2026-27211" } ] }