FKIE_CVE-2021-47312

Vulnerability from fkie_nvd - Published: 2024-05-21 15:15 - Updated: 2026-06-17 04:17
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: Fix dereference of null pointer flow In the case where chain->flags & NFT_CHAIN_HW_OFFLOAD is false then nft_flow_rule_create is not called and flow is NULL. The subsequent error handling execution via label err_destroy_flow_rule will lead to a null pointer dereference on flow when calling nft_flow_rule_destroy. Since the error path to err_destroy_flow_rule has to cater for null and non-null flows, only call nft_flow_rule_destroy if flow is non-null to fix this issue. Addresses-Coverity: ("Explicity null dereference")
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19aPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19aPatch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3Patch
Impacted products
Vendor Product Version
linux linux_kernel *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/netfilter/nf_tables_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "70a5a1950cca02c5cd161bb3846b4d983eed97d3",
              "status": "affected",
              "version": "09b1f676e2e0bbff67c568672c565c6f31470157",
              "versionType": "git"
            },
            {
              "lessThan": "4ca041f919f13783b0b03894783deee00dbca19a",
              "status": "affected",
              "version": "3c5e44622011b9ea21bd425875dcccfc9a158f5f",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/netfilter/nf_tables_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5.13.5",
              "status": "affected",
              "version": "5.13.2",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "8BF6AAC6-D649-4E4F-98AE-B880144C2196",
              "versionEndExcluding": "5.13.5",
              "versionStartIncluding": "5.13.2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: Fix dereference of null pointer flow\n\nIn the case where chain-\u003eflags \u0026 NFT_CHAIN_HW_OFFLOAD is false then\nnft_flow_rule_create is not called and flow is NULL. The subsequent\nerror handling execution via label err_destroy_flow_rule will lead\nto a null pointer dereference on flow when calling nft_flow_rule_destroy.\nSince the error path to err_destroy_flow_rule has to cater for null\nand non-null flows, only call nft_flow_rule_destroy if flow is non-null\nto fix this issue.\n\nAddresses-Coverity: (\"Explicity null dereference\")"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: nf_tables: corrige la desreferencia del flujo de puntero null. En el caso de que chain-\u0026gt;flags \u0026amp; NFT_CHAIN_HW_OFFLOAD sea falso, no se llama a nft_flow_rule_create y el flujo es NULL. La ejecuci\u00f3n posterior del manejo de errores a trav\u00e9s de la etiqueta err_destroy_flow_rule dar\u00e1 lugar a una desreferencia del puntero null en el flujo al llamar a nft_flow_rule_destroy. Dado que la ruta de error a err_destroy_flow_rule tiene que atender flujos nulos y no nulos, solo llame a nft_flow_rule_destroy si el flujo no es nulo para solucionar este problema. Direcciones-Cobertura: (\"Desreferencia nula expl\u00edcita\")"
    }
  ],
  "id": "CVE-2021-47312",
  "lastModified": "2026-06-17T04:17:10.103",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "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"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-47312",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-05-29T18:11:18.013824Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-05-21T15:15:18.660",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19a"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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