FKIE_CVE-2021-38209

Vulnerability from fkie_nvd - Published: 2021-08-08 20:15 - Updated: 2026-06-17 04:01
Severity
3.3 (Low) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Summary
net/netfilter/nf_conntrack_standalone.c in the Linux kernel before 5.12.2 allows observation of changes in any net namespace because these changes are leaked into all other net namespaces. This is related to the NF_SYSCTL_CT_MAX, NF_SYSCTL_CT_EXPECT_MAX, and NF_SYSCTL_CT_BUCKETS sysctls.
References
cve@mitre.orghttps://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.2Mailing List, Patch, Vendor Advisory
cve@mitre.orghttps://github.com/torvalds/linux/commit/2671fa4dc0109d3fb581bc3078fdf17b5d9080f6Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.2Mailing List, Patch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/torvalds/linux/commit/2671fa4dc0109d3fb581bc3078fdf17b5d9080f6Patch, Third Party Advisory
Impacted products
Vendor Product Version
linux linux_kernel *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "280A377E-707F-4C8E-B457-5FD215570D0D",
              "versionEndExcluding": "5.12.2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "net/netfilter/nf_conntrack_standalone.c in the Linux kernel before 5.12.2 allows observation of changes in any net namespace because these changes are leaked into all other net namespaces. This is related to the NF_SYSCTL_CT_MAX, NF_SYSCTL_CT_EXPECT_MAX, and NF_SYSCTL_CT_BUCKETS sysctls."
    },
    {
      "lang": "es",
      "value": "El archivo net/netfilter/nf_conntrack_standalone.c en el kernel de Linux versiones anteriores a 5.12.2, permite la observaci\u00f3n de cambios en cualquier espacio de nombres de red porque estos cambios son filtrados a todos los dem\u00e1s espacios de nombres de red.\u0026#xa0;Esto est\u00e1 relacionado con los sysctls NF_SYSCTL_CT_MAX, NF_SYSCTL_CT_EXPECT_MAX y NF_SYSCTL_CT_BUCKETS"
    }
  ],
  "id": "CVE-2021-38209",
  "lastModified": "2026-06-17T04:01:46.067",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "LOW",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "LOCAL",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 2.1,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "NONE",
          "vectorString": "AV:L/AC:L/Au:N/C:P/I:N/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "NONE",
          "baseScore": 3.3,
          "baseSeverity": "LOW",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 1.4,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-08-08T20:15:07.423",
  "references": [
    {
      "source": "cve@mitre.org",
      "tags": [
        "Mailing List",
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.2"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/torvalds/linux/commit/2671fa4dc0109d3fb581bc3078fdf17b5d9080f6"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.2"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/torvalds/linux/commit/2671fa4dc0109d3fb581bc3078fdf17b5d9080f6"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-203"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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