{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-64475",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-64475"
  ],
  "published": "2026-07-25T08:51:45Z",
  "summary": "vfio/pci: Release the VGA arbiter client on register_device() failure",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/pci: Release the VGA arbiter client on register_device() failure\n\nThe re-order in the Fixes commit below displaced vfio_pci_vga_init() as\nthe last failure point of what is now vfio_pci_core_register_device()\nwithout introducing an unwind for the VGA arbiter registration.\n\nIn current kernels this is mostly benign because vfio_pci_set_decode()\nonly uses pci_dev state, but the original failure path could leave a\ncallback with a freed vdev cookie.  The stale registration also becomes\nunsafe again once the callback follows drvdata to the vfio device.\n\nAdd the required VGA unwind callout.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/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": "6.1.178",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-64475"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0f2a35a0c7ea7da347b814750eaa78adf3582381"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8d65decde9afd2bd78bcfffdc0df73b82a0b5509"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ef4c38d30b3744e89eb5048218904bb629ea8d47"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9e0a3f642e607848669235f5069f35640abbfc88"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/42d758a09d2c46c42357ecde9a5492f015bde2e5"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/52adb2dff7ce3d8430e2bdc5988b618a430def85"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/278a5659c391fe5afe5f9ce1bad1fd24e90144f1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/daedde7f024ecf88bc8e832ed40cf2c795f0796a"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-17T05:24:08Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 8.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The flaw is triggered through local `/dev/vga_arbiter` operations or accesses to a delegated VFIO VGA region; it is not directly network-reachable. The VGA-arbiter character-device interface is documented in the [kernel documentation](https://docs.kernel.org/gpu/vgaarbiter.html).\nAC:L - Once failed VFIO registration leaves the stale callback, a single first-use VGA lock or legacy VGA access invokes it. No race must be won, and the attacker controls the triggering access.\nPR:L - The failed bind may arise from boot or privileged orchestration, but the subsequent callback path has no capability check and can be triggered by a video-group user, delegated VFIO process, or VM tenant. Real host-root privileges are therefore not required in a reasonable deployment.\nUI:N - The attacker directly performs the VGA-arbiter or VFIO-region access, with no victim action required during exploitation. Prior system configuration or automated device binding is not user interaction.\nS:C - With VFIO GPU passthrough, QEMU translates guest legacy-VGA accesses into VFIO `pread()` and `pwrite()` operations, allowing a guest to activate the stale host callback and potentially compromise the host kernel across the VM boundary, as shown by [QEMU\u2019s VFIO VGA implementation](https://gitlab.com/qemu-project/qemu/-/blob/e5b3a241 81ea0cebf1c5b20f44d016311b7048f0/hw/vfio/pci.c).\nC:H - Historical affected branches retain a callback cookie pointing to a freed `struct vfio_pci_device`; reclaiming that allocation can control its embedded `pdev` pointer and redirect kernel pointer dereferences. Under conservative UAF assessment, this can enable disclosure of arbitrary host memory.\nI:H - The dangling object and potentially stale module callback create exploitable memory-lifetime corruption that can be heap-shaped toward control-flow hijacking or arbitrary kernel modification. Successful exploitation can therefore execute code in the host kernel.\nA:H - An invalid reclaimed `pdev` or unloaded callback target can immediately produce a kernel page fault, oops, or panic. The trigger requires only one attacker-controlled VGA access after the stale registration exists."
    }
  }
}