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        "state": "PUBLISHED",
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        "dateReserved": "2026-09-18T18:12:23.908Z",
        "datePublished": "2026-09-25T13:36:17.597Z",
        "dateUpdated": "2026-09-25T13:50:26.440Z"
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            "title": "Qemu-kvm: 9pfs: use-after-free race in tlcreate/twalk allows vm guest escape",
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                        "attackComplexity": "LOW",
                        "attackVector": "LOCAL",
                        "availabilityImpact": "HIGH",
                        "baseScore": 8.8,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "LOW",
                        "scope": "CHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
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                    "value": "A use-after-free vulnerability was found in QEMU's 9pfs subsystem. A race condition between the main thread and a worker thread when processing concurrent Tlcreate and Twalk requests allows a malicious guest user to craft a fid path containing stale heap data, bypassing directory traversal restrictions and escaping the shared directory boundary. This can lead to arbitrary host file read/write and code execution (VM escape) as the QEMU process user."
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                    "vendor": "Red Hat",
                    "product": "Red Hat OpenStack Platform 13 (Queens)",
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                    "packageName": "qemu-kvm-rhev",
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                            "cweId": "CWE-416",
                            "description": "Use After Free",
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                {
                    "lang": "en",
                    "value": "Do not configure 9pfs/VirtFS filesystem sharing (-fsdev, -virtfs) on affected QEMU instances. If host-guest file sharing is required, use virtio-fs (virtiofsd) as an alternative, which does not use the vulnerable 9pfs code path."
                }
            ],
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                    "lang": "en",
                    "time": "2026-09-22T00:00:00.000Z",
                    "value": "Reported to Red Hat."
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                    "time": "2026-09-22T00:00:00.000Z",
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