FKIE_CVE-2021-46952

Vulnerability from fkie_nvd - Published: 2024-02-27 19:04 - Updated: 2026-06-17 04:15
Severity
7.1 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: NFS: fs_context: validate UDP retrans to prevent shift out-of-bounds Fix shift out-of-bounds in xprt_calc_majortimeo(). This is caused by a garbage timeout (retrans) mount option being passed to nfs mount, in this case from syzkaller. If the protocol is XPRT_TRANSPORT_UDP, then 'retrans' is a shift value for a 64-bit long integer, so 'retrans' cannot be >= 64. If it is >= 64, fail the mount and return an error.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/2f3380121d49e829fb73ba86240c181bc32ad897Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3d0163821c035040a46d816a42c0780f0f0a30a8Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/96fa26b74cdcf9f5c98996bf36bec9fb5b19ffe2Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c09f11ef35955785f92369e25819bf0629df2e59Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/2f3380121d49e829fb73ba86240c181bc32ad897Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/3d0163821c035040a46d816a42c0780f0f0a30a8Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/96fa26b74cdcf9f5c98996bf36bec9fb5b19ffe2Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/c09f11ef35955785f92369e25819bf0629df2e59Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/fs_context.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "96fa26b74cdcf9f5c98996bf36bec9fb5b19ffe2",
              "status": "affected",
              "version": "9954bf92c0cddd50a2a470be302e1c1ffdf21d42",
              "versionType": "git"
            },
            {
              "lessThan": "2f3380121d49e829fb73ba86240c181bc32ad897",
              "status": "affected",
              "version": "9954bf92c0cddd50a2a470be302e1c1ffdf21d42",
              "versionType": "git"
            },
            {
              "lessThan": "3d0163821c035040a46d816a42c0780f0f0a30a8",
              "status": "affected",
              "version": "9954bf92c0cddd50a2a470be302e1c1ffdf21d42",
              "versionType": "git"
            },
            {
              "lessThan": "c09f11ef35955785f92369e25819bf0629df2e59",
              "status": "affected",
              "version": "9954bf92c0cddd50a2a470be302e1c1ffdf21d42",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/fs_context.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.6"
            },
            {
              "lessThan": "5.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.36",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.11.*",
              "status": "unaffected",
              "version": "5.11.20",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.12.*",
              "status": "unaffected",
              "version": "5.12.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "9F676E27-91BA-4675-B518-89C5729CC97C",
              "versionEndExcluding": "5.10.36",
              "versionStartIncluding": "5.6.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "EFB425F0-C28C-4B44-8B4C-AD512AA832DE",
              "versionEndExcluding": "5.11.20",
              "versionStartIncluding": "5.11.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "C3814FA3-8141-4313-A852-8C4212BE12AD",
              "versionEndExcluding": "5.12.3",
              "versionStartIncluding": "5.12.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFS: fs_context: validate UDP retrans to prevent shift out-of-bounds\n\nFix shift out-of-bounds in xprt_calc_majortimeo(). This is caused\nby a garbage timeout (retrans) mount option being passed to nfs mount,\nin this case from syzkaller.\n\nIf the protocol is XPRT_TRANSPORT_UDP, then \u0027retrans\u0027 is a shift\nvalue for a 64-bit long integer, so \u0027retrans\u0027 cannot be \u003e= 64.\nIf it is \u003e= 64, fail the mount and return an error."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: NFS: fs_context: valida las retransmisiones UDP para evitar cambios fuera de los l\u00edmites. Corrige cambios fuera de los l\u00edmites en xprt_calc_majortimeo(). Esto se debe a que se pasa una opci\u00f3n de montaje de tiempo de espera de basura (retransmisi\u00f3n) al montaje nfs, en este caso desde syzkaller. Si el protocolo es XPRT_TRANSPORT_UDP, entonces \u0027retrans\u0027 es un valor de desplazamiento para un entero largo de 64 bits, por lo que \u0027retrans\u0027 no puede ser \u0026gt;= 64. Si es \u0026gt;= 64, falla el montaje y devuelve un error."
    }
  ],
  "id": "CVE-2021-46952",
  "lastModified": "2026-06-17T04:15:57.717",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.2,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-46952",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-02-27T20:13:18.077870Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-02-27T19:04:06.517",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/2f3380121d49e829fb73ba86240c181bc32ad897"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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      "url": "https://git.kernel.org/stable/c/3d0163821c035040a46d816a42c0780f0f0a30a8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
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      "url": "https://git.kernel.org/stable/c/96fa26b74cdcf9f5c98996bf36bec9fb5b19ffe2"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/c09f11ef35955785f92369e25819bf0629df2e59"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/2f3380121d49e829fb73ba86240c181bc32ad897"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3d0163821c035040a46d816a42c0780f0f0a30a8"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/96fa26b74cdcf9f5c98996bf36bec9fb5b19ffe2"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/c09f11ef35955785f92369e25819bf0629df2e59"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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