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FKIE_CVE-2021-3178

Vulnerability from fkie_nvd - Published: 2021-01-19 07:15 - Updated: 2026-06-17 04:04
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Summary
fs/nfsd/nfs3xdr.c in the Linux kernel through 5.10.8, when there is an NFS export of a subdirectory of a filesystem, allows remote attackers to traverse to other parts of the filesystem via READDIRPLUS. NOTE: some parties argue that such a subdirectory export is not intended to prevent this attack; see also the exports(5) no_subtree_check default behavior
References
cve@mitre.orghttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=51b2ee7d006a736a9126e8111d1f24e4fd0afaa6Mailing List, Patch, Vendor Advisory
cve@mitre.orghttps://lists.debian.org/debian-lts-announce/2021/03/msg00010.htmlMailing List, Third Party Advisory
cve@mitre.orghttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5SGB7TNDVQEOJ7NVTGX56UWHDNQM5TRC/
cve@mitre.orghttps://patchwork.kernel.org/project/linux-nfs/patch/20210111210129.GA11652%40fieldses.org/
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=51b2ee7d006a736a9126e8111d1f24e4fd0afaa6Mailing List, Patch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2021/03/msg00010.htmlMailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5SGB7TNDVQEOJ7NVTGX56UWHDNQM5TRC/
af854a3a-2127-422b-91ae-364da2661108https://patchwork.kernel.org/project/linux-nfs/patch/20210111210129.GA11652%40fieldses.org/
Impacted products
Vendor Product Version
linux linux_kernel *
fedoraproject fedora 33
debian debian_linux 9.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
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              "matchCriteriaId": "6F39D11B-E596-4D1C-AA3A-29C3D33CDC0D",
              "versionEndIncluding": "5.10.8",
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  ],
  "cveTags": [
    {
      "sourceIdentifier": "cve@mitre.org",
      "tags": [
        "disputed"
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    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "fs/nfsd/nfs3xdr.c in the Linux kernel through 5.10.8, when there is an NFS export of a subdirectory of a filesystem, allows remote attackers to traverse to other parts of the filesystem via READDIRPLUS. NOTE: some parties argue that such a subdirectory export is not intended to prevent this attack; see also the exports(5) no_subtree_check default behavior"
    },
    {
      "lang": "es",
      "value": "** EN DISPUTA ** en el archivo fs/nfsd/nfs3xdr.c en el kernel de Linux versiones hasta 5.10.8, cuando se presenta una exportaci\u00f3n NFS de un subdirectorio de un sistema de archivos, permite a atacantes remotos saltar otras partes del sistema de archivos por medio de READDIRPLUS.\u0026#xa0;NOTA: algunas terceros argumentan que tal exportaci\u00f3n de subdirectorios no intenta impedir este ataque;\u0026#xa0;v\u00e9ase tambi\u00e9n el comportamiento predeterminado de no_subtree_check de exports(5)"
    }
  ],
  "id": "CVE-2021-3178",
  "lastModified": "2026-06-17T04:04:47.713",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "NONE",
          "baseScore": 5.5,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:L/Au:S/C:P/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 8.0,
        "impactScore": 4.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
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          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N",
          "version": "3.1"
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        "impactScore": 5.2,
        "source": "nvd@nist.gov",
        "type": "Primary"
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  "published": "2021-01-19T07:15:13.443",
  "references": [
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      "source": "cve@mitre.org",
      "tags": [
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      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=51b2ee7d006a736a9126e8111d1f24e4fd0afaa6"
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    },
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    },
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    }
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  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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