{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/iommu/generic_pt/iommu_pt.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "00850f41da24423587abd6124a790dd4f12bcef3",
              "status": "affected",
              "version": "dcd6a011a8d523a114af2360a8753de5bd60c139",
              "versionType": "git"
            },
            {
              "lessThan": "8ef3f77c440005c7f04229a75976bfc078364247",
              "status": "affected",
              "version": "dcd6a011a8d523a114af2360a8753de5bd60c139",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/iommu/generic_pt/iommu_pt.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "lessThan": "6.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.11",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommupt: Check for missing PAGE_SIZE in the pgsize_bitmap\n\nSashiko pointed out that the driver could drop PAGE_SIZE from the\npgsize_bitmap. That is technically allowed but nothing does it, and\nsuch an iommu_domain would not be used with the DMA API today.\n\nStill, it is against the design and it is trivial to fix up. Lift\nthe PT_WARN_ON to the if branch and just skip the fast path."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.4,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is in `map_range()` inside the generic IOMMU page-table path, reached only via local kernel interfaces (`iommu_map()` \u2192 `iommu_map_nosync()` \u2192 `pt-\u003eops-\u003emap_range()`), primarily through `/dev/iommufd` or `/dev/vfio/*` ioctls during device passthrough mapping setup. There is no network-facing entry point.\nAC:L - Once an IOMMU paging domain exists with `PAGE_SIZE` cleared from `pgsize_bitmap`, any `iommu_map()`/`IOMMU_IOAS_MAP` call mapping a single page reliably takes the buggy fast path; the attacker controls mapping requests and needs no races or special memory layout.\nPR:L - Exploitation requires local ability to create IOMMU mappings for a passthrough device (IOMMUFD/VFIO ioctl access and device group permissions), which is available to unprivileged tenants on cloud GPU/NIC passthrough hosts without host root, even though opening `/dev/iommufd` alone is insufficient.\nUI:N - Triggering the flaw is entirely programmatic through IOMMU mapping ioctls; no victim interaction such as mounting a filesystem or opening a file is required.\nS:C - Incorrect leaf PTE installation on an IOMMU domain can break DMA isolation, allowing a device to read/write host physical memory outside its authorized mappings\u2014an IOMMU/DMA security-boundary bypass per kernel CVSS guidance.\nC:H - Malformed or policy-violating IOMMU page-table entries can cause a DMA-capable device to read arbitrary host physical memory beyond the intended IOVA window, constituting arbitrary memory disclosure through the IOMMU bypass primitive.\nI:H - The fast path installs `PAGE_SHIFT` leaf entries even when `PAGE_SIZE` is excluded from `pgsize_bitmap`, corrupting IOMMU translation state and enabling a DMA device to write to unauthorized host physical pages.\nA:N - The flaw corrupts IOMMU translation entries rather than causing a kernel oops, panic, or hang; availability impact is not a primary or reliable outcome of triggering this bug."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:39:45.883Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/00850f41da24423587abd6124a790dd4f12bcef3"
        },
        {
          "url": "https://git.kernel.org/stable/c/8ef3f77c440005c7f04229a75976bfc078364247"
        }
      ],
      "title": "iommupt: Check for missing PAGE_SIZE in the pgsize_bitmap",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64151",
    "datePublished": "2026-07-19T15:40:40.643Z",
    "dateReserved": "2026-07-19T07:54:57.037Z",
    "dateUpdated": "2026-08-05T12:39:45.883Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}