{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-93782",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-93782"
  ],
  "published": "2026-09-24T16:08:25Z",
  "summary": "vhost-scsi: flush backend after device ioctls",
  "details": "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.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.189",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-93782"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6436411203d8c702ffc055700f1a6bde488ff681"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/cec088285adcc7ae23c119b6bbdb22270dc2de8f"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/e0bf6bed528693a6b32439ab122b34a34b66d96f"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/be2636e1b21fe860db918152abf2932638d06ed7"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/981c97d09c6b9560bb12dcc41f11ce59b1a48e97"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6c1b802e36b05ebd9d41686c4dce6f06966af469"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/22598f55a4c2b510b3df5e69e563387a963222ae"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-10-03T11:04:09Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "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."
    }
  }
}