{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2"
            },
            {
              "fixed": "685b10dd0e32c7782cead16c8cf055c609678583"
            },
            {
              "fixed": "16eaba5aa89c04eea125905bb8f988c1897f4f29"
            },
            {
              "fixed": "09dba37eee70d0596e26645015f1aa95a9848e9d"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.93"
            },
            {
              "fixed": "7.0.12"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.93"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "7.0.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64523.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/handshake: Take a long-lived file reference at submit\n\nhandshake_nl_accept_doit() needs the file pointer backing\nreq-\u003ehr_sk-\u003esk_socket to survive the window between\nhandshake_req_next() and the subsequent FD_PREPARE() and get_file().\nThe submit-side sock_hold() does not provide that.  sk_refcnt keeps\nstruct sock alive, but struct socket is owned by sock-\u003efile: when\nthe consumer fputs the last file reference, sock_release() tears\nthe socket down regardless of any sock_hold.\n\nAdd an hr_file pointer to struct handshake_req and acquire an\nexplicit reference on sock-\u003efile during handshake_req_submit().\nhandshake_complete() and handshake_req_cancel() release the\nreference on the completion-bit-winning path.\n\nThe submit error path must also release the file reference, but\nafter rhashtable insertion a concurrent handshake_req_cancel() can\ndiscover the request and race the error path.  Gate the error-path\ncleanup -- sk_destruct restoration, fput, and request destruction\n-- with test_and_set_bit(HANDSHAKE_F_REQ_COMPLETED), the same\nserialization handshake_complete() and handshake_req_cancel()\nalready use.  When cancel has already claimed ownership, the submit\nerror path returns without touching the request; socket teardown\nhandles final destruction.\n\nThe accept-side dereferences are not yet retargeted; that change\ncomes in the next patch.",
  "id": "CVE-2026-64523",
  "modified": "2026-07-27T03:56:43.828278905Z",
  "published": "2026-07-25T09:20:47.606Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/09dba37eee70d0596e26645015f1aa95a9848e9d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/16eaba5aa89c04eea125905bb8f988c1897f4f29"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/685b10dd0e32c7782cead16c8cf055c609678583"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64523.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64523"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "net/handshake: Take a long-lived file reference at submit"
}