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    "distribution": {
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        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Cloud Linux Inc. and provide a link to the original.",
        "title": "Terms of Use"
      }
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      "contact_details": "https://tuxcare.com/contact/",
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        "url": "https://security.tuxcare.com/csaf/v2/els_os/ubuntu16.04els/vex/2025/cve-2025-39688-els_os-ubuntu16_04els.json"
      }
    ],
    "title": "Security update on CVE-2025-39688",
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      "generator": {
        "date": "2025-12-23T22:15:38Z",
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      "id": "CVE-2025-39688-ELS_OS-UBUNTU16.04ELS",
      "initial_release_date": "2025-04-18T00:00:00Z",
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          "number": "1",
          "summary": "Initial version"
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        {
          "date": "2025-07-21T07:33:22Z",
          "number": "2",
          "summary": "Official Publication"
        },
        {
          "date": "2025-12-23T22:15:38Z",
          "number": "3",
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  "vulnerabilities": [
    {
      "cve": "CVE-2025-39688",
      "cwe": {
        "id": "CWE-99",
        "name": "Improper Control of Resource Identifiers ('Resource Injection')"
      },
      "notes": [
        {
          "category": "description",
          "text": "In the Linux kernel, the following vulnerability has been resolved:\nnfsd: allow SC_STATUS_FREEABLE when searching via nfs4_lookup_stateid()\nThe pynfs DELEG8 test fails when run against nfsd. It acquires a\ndelegation and then lets the lease time out. It then tries to use the\ndeleg stateid and expects to see NFS4ERR_DELEG_REVOKED, but it gets\nbad NFS4ERR_BAD_STATEID instead.\nWhen a delegation is revoked, it's initially marked with\nSC_STATUS_REVOKED, or SC_STATUS_ADMIN_REVOKED and later, it's marked\nwith the SC_STATUS_FREEABLE flag, which denotes that it is waiting for\ns FREE_STATEID call.\nnfs4_lookup_stateid() accepts a statusmask that includes the status\nflags that a found stateid is allowed to have. Currently, that mask\nnever includes SC_STATUS_FREEABLE, which means that revoked delegations\nare (almost) never found.\nAdd SC_STATUS_FREEABLE to the always-allowed status flags, and remove it\nfrom nfsd4_delegreturn() since it's now always implied.",
          "title": "Vulnerability description"
        },
        {
          "category": "general",
          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.",
          "title": "CVSS score applicability"
        }
      ],
      "product_status": {
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      "references": [
        {
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          "summary": "Canonical URL",
          "url": "https://cve.tuxcare.com/els/cve/CVE-2025-39688"
        }
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      "release_date": "2025-04-18T00:00:00",
      "scores": [
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            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 5.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
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      "threats": [
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          "category": "impact",
          "details": "Medium"
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}