{
  "id": "CVE-2021-27861",
  "sourceIdentifier": "cret@cert.org",
  "published": "2022-09-27T19:15:09.330",
  "lastModified": "2022-10-12T13:15:10.550",
  "vulnStatus": "Modified",
  "descriptions": [
    {
      "lang": "en",
      "value": "Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length (and optionally VLAN0 headers)"
    },
    {
      "lang": "es",
      "value": "Las capacidades de filtrado de red de capa 2, como la protecci\u00f3n RA de IPv6, pueden omitirse usando encabezados LLC/SNAP con una longitud no v\u00e1lida (y, opcionalmente, encabezados VLAN0)"
    }
  ],
  "metrics": {
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        "type": "Primary",
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          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE",
          "baseScore": 4.7,
          "baseSeverity": "MEDIUM"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4
      }
    ]
  },
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "type": "Primary",
      "description": [
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          "value": "CWE-290"
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    {
      "source": "cret@cert.org",
      "type": "Secondary",
      "description": [
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          "lang": "en",
          "value": "CWE-130"
        },
        {
          "lang": "en",
          "value": "CWE-290"
        }
      ]
    }
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  "references": [
    {
      "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/",
      "source": "cret@cert.org"
    },
    {
      "url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/",
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}