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vuln-cve/data/2026/93xxx/CVE-2026-93782.json
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{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2026-93782",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2026-09-18T17:59:28.788Z",
"datePublished": "2026-09-24T16:02:14.457Z",
"dateUpdated": "2026-10-03T10:57:16.951Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-10-03T10:57:16.951Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvhost-scsi: flush backend after device ioctls\n\nvhost-scsi translates guest response descriptors into userspace iovecs\nwhen commands are submitted. Target-core completes those commands\nasynchronously, so VHOST_SET_MEM_TABLE can replace the memory table while\nan in-flight command still retains response iovecs translated through the\nold table.\n\nIf the old mapping is reused after VHOST_SET_MEM_TABLE returns, command\ncompletion can write the response to an unrelated userspace object.\n\nFlush the vhost-scsi backend after vhost_dev_ioctl() handles a device\nioctl. This waits for in-flight commands that can still use the old\nresponse iovecs before the ioctl returns."
}
],
"metrics": [
{
"cvssV3_1": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
"baseScore": 7.8,
"baseSeverity": "HIGH"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The missing flush is in vhost_scsi_ioctl() after vhost_dev_ioctl() handles VHOST_SET_MEM_TABLE via vhost_set_memory() on /dev/vhost-scsi; the retained pointers are tvc_resp_iovs filled by vhost_scsi_setup_resp_iovs() from vhost_get_vq_desc() on the local virtio-scsi virtqueue, not a network PDU.\nAC:H - A guest can leave commands in target-core via vhost_scsi_handle_vq()->vhost_scsi_target_queue_cmd()->target_submit(), but cannot call VHOST_SET_MEM_TABLE; only the VMM issues that ioctl (memory hotplug or live migration), so the replacement that makes old HVAs reusable is outside the attacker's control.\nPR:L - The attacker is a VM tenant sending virtio-scsi I/O that plants those tvc_resp_iovs; vhost_scsi_open() and vhost_scsi_ioctl() have no capable() check, and the already-attached LIO tpg (VHOST_SCSI_SET_ENDPOINT by QEMU) lets that guest I/O run without host root.\nUI:N - The guest plants in-flight commands by kicking its own virtqueue; no other user must mount an image or open a file. A later VMM VHOST_SET_MEM_TABLE is ordinary hypervisor memory-listener bookkeeping, not a tricked interactive action.\nS:C - vhost_scsi_complete_cmd_work() copy_to_iter()s virtio_scsi_cmd_resp through stale tvc_resp_iovs (and vhost_scsi_copy_sgl_to_iov() through a stale read_iter) into the host QEMU mm, so guest-originated completion corrupts VMM userspace across the KVM guest-to-host boundary.\nC:H - After QEMU reuses the old HVA, completion writes into unrelated VMM objects; the copied_iov READ path (vhost_scsi_copy_iov_to_sgl() dup_iter, then vhost_scsi_copy_sgl_to_iov()) can copy LUN data into that remapped heap, which is leverageable to disclose host memory back to the guest.\nI:H - copy_to_iter() of the packed virtio_scsi_cmd_resp plus, when vhost_scsi_map_to_sgl() falls back to vhost_scsi_copy_iov_to_sgl() for misaligned I/O with sgl_count>BIO_MAX_VECS, a guest-influenced READ payload into the remapped HVA, corrupting QEMU heap objects and enabling VMM control-flow hijack.\nA:H - A reused QEMU mapping hit by that completion write corrupts VMM heap metadata and aborts QEMU, terminating the VM; an unmapped old HVA only hits the \"Faulted on virtio_scsi_cmd_resp\" path, but reuse after VHOST_SET_MEM_TABLE is the contract the ioctl was supposed to guarantee."
}
]
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/vhost/scsi.c"
],
"versions": [
{
"version": "057cbf49a1f08297877e46c82f707b1bfea806a8",
"lessThan": "6436411203d8c702ffc055700f1a6bde488ff681",
"status": "affected",
"versionType": "git"
},
{
"version": "057cbf49a1f08297877e46c82f707b1bfea806a8",
"lessThan": "cec088285adcc7ae23c119b6bbdb22270dc2de8f",
"status": "affected",
"versionType": "git"
},
{
"version": "057cbf49a1f08297877e46c82f707b1bfea806a8",
"lessThan": "e0bf6bed528693a6b32439ab122b34a34b66d96f",
"status": "affected",
"versionType": "git"
},
{
"version": "057cbf49a1f08297877e46c82f707b1bfea806a8",
"lessThan": "be2636e1b21fe860db918152abf2932638d06ed7",
"status": "affected",
"versionType": "git"
},
{
"version": "057cbf49a1f08297877e46c82f707b1bfea806a8",
"lessThan": "981c97d09c6b9560bb12dcc41f11ce59b1a48e97",
"status": "affected",
"versionType": "git"
},
{
"version": "057cbf49a1f08297877e46c82f707b1bfea806a8",
"lessThan": "6c1b802e36b05ebd9d41686c4dce6f06966af469",
"status": "affected",
"versionType": "git"
},
{
"version": "057cbf49a1f08297877e46c82f707b1bfea806a8",
"lessThan": "22598f55a4c2b510b3df5e69e563387a963222ae",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/vhost/scsi.c"
],
"versions": [
{
"version": "3.6",
"status": "affected"
},
{
"version": "0",
"lessThan": "3.6",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.10.271",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.15.222",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.1.189",
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.6.158",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.12.111",
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.18.53",
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "7.2",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.6",
"versionEndExcluding": "5.10.271"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.6",
"versionEndExcluding": "5.15.222"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.6",
"versionEndExcluding": "6.1.189"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.6",
"versionEndExcluding": "6.6.158"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.6",
"versionEndExcluding": "6.12.111"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.6",
"versionEndExcluding": "6.18.53"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.6",
"versionEndExcluding": "7.2"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/6436411203d8c702ffc055700f1a6bde488ff681"
},
{
"url": "https://git.kernel.org/stable/c/cec088285adcc7ae23c119b6bbdb22270dc2de8f"
},
{
"url": "https://git.kernel.org/stable/c/e0bf6bed528693a6b32439ab122b34a34b66d96f"
},
{
"url": "https://git.kernel.org/stable/c/be2636e1b21fe860db918152abf2932638d06ed7"
},
{
"url": "https://git.kernel.org/stable/c/981c97d09c6b9560bb12dcc41f11ce59b1a48e97"
},
{
"url": "https://git.kernel.org/stable/c/6c1b802e36b05ebd9d41686c4dce6f06966af469"
},
{
"url": "https://git.kernel.org/stable/c/22598f55a4c2b510b3df5e69e563387a963222ae"
}
],
"title": "vhost-scsi: flush backend after device ioctls",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
}
}