{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-80552",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-80552"
  ],
  "published": "2026-08-26T14:37:59Z",
  "summary": "s390/vfio_ccw: Ensure index for read/write regions are within range",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/vfio_ccw: Ensure index for read/write regions are within range\n\nThe introduction of the capability chain rightly clamped the\nregion indexes to the range of the capabilities itself, but\nneglected to do so for the existing read/write regions which\nshould also be enforced.",
  "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": "6.1.184",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-80552"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/3acbedf5c0b8e0971f0de423c05cc02bbf6ddb99"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d3b1e38404b22df5a1f93019f2bb656feaad5ae3"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/79ea5e0c4c8a9842ae85f45062d947b3297dfc07"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d597fa1273802941c7801202135976fecc29672b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/649badf3a2fd8929e40198603a2cb21b74c21700"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/988d9b5be3c2c4baf9457ce8e11b477e13eb9fcf"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9f5f9a78fedc45bc29d6a0a64e3a3472361afae5"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-27T12:40:42Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 8.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The flaw is reached only via local VFIO mediated-device syscalls (read/write on a vfio-ccw device fd and VFIO_DEVICE_GET_REGION_INFO ioctl); vfio-ccw has no network, Bluetooth, or physical-bus entry point.\nAC:L - An attacker with an open vfio-ccw fd can deterministically supply crafted file offsets encoding out-of-range region indexes to read/write/ioctl handlers, or race close/teardown against region access, without depending on uncontrollable kernel layout or rare timing.\nPR:L - Exploitation requires an opened vfio-ccw mdev device fd (typical QEMU/libvirt VM operator or delegated /dev/vfio holder on IBM Z passthrough); mdev creation is admin setup, but triggering the OOB paths needs only that delegated VFIO client, not init-namespace root.\nUI:N - No separate victim action is required beyond the attacker (or their QEMU process) issuing crafted VFIO read/write/ioctl calls on an already-assigned passthrough device; no mount, click, or other user cooperation is needed at trigger time.\nS:C - On IBM Z/LinuxONE, vfio-ccw exists to pass DASD/CCW subchannels into KVM guests; OOB region indexing in host read/write/ioctl corrupts hypervisor kernel memory outside the guest VM security boundary, enabling cross-tenant host compromise.\nC:H - Missing bounds checks and array_index_nospec on region[i] let out-of-range indexes make copy_to_user read from adjacent kernel heap/metadata beyond the region array, providing arbitrary kernel memory disclosure primitives.\nI:H - Out-of-range region indexes route copy_from_user writes to wrong kernel objects (cmd_region, schib_region, crw_region, or adjacent heap), enabling heap corruption and exploitable arbitrary kernel write or control-flow hijack.\nA:H - Out-of-bounds access to freed or invalid region metadata during concurrent device close, or corrupting vfio_ccw_private adjacent structures, can immediately oops or panic the host kernel."
    }
  }
}