{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a85f31052bce52111b4e9d5a536003481d0421d0"
            },
            {
              "fixed": "722869fcff598fad20d5ab79c305897a7534708b"
            },
            {
              "fixed": "7267717f35787167fcce4bc14f6ef3fa06682dcf"
            },
            {
              "fixed": "2564ca2e31bd8ee8348362941af2ee4671e487ca"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.39"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64426.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/nop: fix file reference leak with IOSQE_FIXED_FILE\n\nNOP file-acquisition support choses between a fixed (registered) file and\na normal fget()'d file based on its own IORING_NOP_FIXED_FILE flag in\nsqe-\u003enop_flags. However, a request's REQ_F_FIXED_FILE is set\nindependently from the generic IOSQE_FIXED_FILE sqe flag during request\ninit, before the issue handler runs.\n\nIf a NOP is submitted with IOSQE_FIXED_FILE set (so REQ_F_FIXED_FILE is\nset) but without IORING_NOP_FIXED_FILE, io_nop() takes the normal path\nand grabs a real reference via io_file_get_normal(). On completion,\nio_put_file() only drops the reference when REQ_F_FIXED_FILE is clear,\nso the fget()'d file is never released and leaks:\n\n  BUG: memory leak\n  unreferenced object 0xffff88800f42c240 (size 176):\n    kmem_cache_alloc_noprof+0x358/0x440\n    alloc_empty_file+0x57/0x180\n    path_openat+0x44/0x1e50\n    do_file_open+0x121/0x200\n    do_sys_openat2+0xa7/0x150\n    __x64_sys_openat+0x82/0xf0\n\nDecide between fixed and normal file acquisition from REQ_F_FIXED_FILE,\nthe same way io_assign_file() does for every other opcode, and fold\nIORING_NOP_FIXED_FILE into REQ_F_FIXED_FILE at prep time.",
  "id": "CVE-2026-64426",
  "modified": "2026-07-27T03:56:14.732219954Z",
  "published": "2026-07-25T08:51:03.867Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2564ca2e31bd8ee8348362941af2ee4671e487ca"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/722869fcff598fad20d5ab79c305897a7534708b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7267717f35787167fcce4bc14f6ef3fa06682dcf"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64426.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64426"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "io_uring/nop: fix file reference leak with IOSQE_FIXED_FILE"
}