github - ghsa-4fhf-8ph3-pp6c

ghsa-4fhf-8ph3-pp6c

Vulnerability from github

Published

2022-09-28 00:00

Modified

2025-11-04 21:30

Severity ?

4.7 (Medium) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Details

Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers).

Show details on source website

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{
  "affected": [],
  "aliases": [
    "CVE-2021-27862"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-130",
      "CWE-290"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-09-27T19:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers).",
  "id": "GHSA-4fhf-8ph3-pp6c",
  "modified": "2025-11-04T21:30:27Z",
  "published": "2022-09-28T00:00:18Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-27862"
    },
    {
      "type": "WEB",
      "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP"
    },
    {
      "type": "WEB",
      "url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08"
    },
    {
      "type": "WEB",
      "url": "https://kb.cert.org/vuls/id/855201"
    },
    {
      "type": "WEB",
      "url": "https://standards.ieee.org/ieee/802.2/1048"
    },
    {
      "type": "WEB",
      "url": "https://www.kb.cert.org/vuls/id/855201"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2021-27862 (GCVE-0-2021-27862)

Vulnerability from cvelistv5

Published

2022-09-27 18:40

Modified

2025-11-04 19:12

Severity ?

4.7 (Medium) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

CWE

CWE-130 - Improper Handling of Length Parameter
CWE-290 - Authentication Bypass by Spoofing

Summary

Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers).

References

URL

Tags

	https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/
	https://standards.ieee.org/ieee/802.2/1048/
	https://kb.cert.org/vuls/id/855201
	https://blog.champtar.fr/VLAN0_LLC_SNAP/

Impacted products

Vendor

Product

Version

Version: 802.2h-1997 <

draft-ietf-v6ops-ra-guard-08

Version: 08 <

Show details on NVD website

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-04T19:12:28.789Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://standards.ieee.org/ieee/802.2/1048/"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://kb.cert.org/vuls/id/855201"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/"
          },
          {
            "url": "https://www.kb.cert.org/vuls/id/855201"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "ADJACENT_NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 4.7,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "NONE",
              "integrityImpact": "LOW",
              "privilegesRequired": "NONE",
              "scope": "CHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2021-27862",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-05-21T15:04:33.466068Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-05-21T15:04:40.862Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "802.2",
          "vendor": "IEEE",
          "versions": [
            {
              "lessThanOrEqual": "802.2h-1997",
              "status": "affected",
              "version": "802.2h-1997",
              "versionType": "custom"
            }
          ]
        },
        {
          "product": "draft-ietf-v6ops-ra-guard-08",
          "vendor": "IETF",
          "versions": [
            {
              "lessThanOrEqual": "08",
              "status": "affected",
              "version": "08",
              "versionType": "custom"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Etienne Champetier (@champtar) \u003cchampetier.etienne@gmail.com\u003e"
        }
      ],
      "datePublic": "2022-09-27T00:00:00.000Z",
      "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 Ethernet to Wifi frame conversion (and optionally VLAN0 headers)."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-130",
              "description": "CWE-130 Improper Handling of Length Parameter",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-290",
              "description": "CWE-290: Authentication Bypass by Spoofing",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2022-10-12T00:00:00.000Z",
        "orgId": "37e5125f-f79b-445b-8fad-9564f167944b",
        "shortName": "certcc"
      },
      "references": [
        {
          "url": "https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/"
        },
        {
          "url": "https://standards.ieee.org/ieee/802.2/1048/"
        },
        {
          "url": "https://kb.cert.org/vuls/id/855201"
        },
        {
          "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with an invalid length during Ethernet to Wifi frame translation"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "37e5125f-f79b-445b-8fad-9564f167944b",
    "assignerShortName": "certcc",
    "cveId": "CVE-2021-27862",
    "datePublished": "2022-09-27T18:40:14.712Z",
    "dateReserved": "2021-03-01T00:00:00.000Z",
    "dateUpdated": "2025-11-04T19:12:28.789Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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