Search

Find a vulnerability

Search criteria ⓘ Use this form to refine search results.
Full-text search supports keyword queries with ranking and filtering.
You can combine vendor, product, and sources to narrow results.
Enable “Apply ordering” to sort by date instead of relevance.

    2 vulnerabilities found for catalyst_6509-e_firmware by cisco

    CVE-2021-27853 (GCVE-0-2021-27853)

    Vulnerability from cvelistv5 – Published: 2022-09-27 17:55 – Updated: 2025-11-04 19:12
    VLAI
    Title
    L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers
    Summary
    Layer 2 network filtering capabilities such as IPv6 RA guard or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers.
    Severity
    4.7 (Medium)
    CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
    SSVC
    Exploitation: none Automatable: no Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-290 - Authentication Bypass by Spoofing
    Assigner
    References
    Impacted products
    Vendor Product Version
    IEEE 802.2 Affected: 802.2h-1997 , ≤ 802.2h-1997 (custom)
    		Create a notification for this product.
    IETF draft-ietf-v6ops-ra-guard Affected: 08 , ≤ 08 (custom)
    		Create a notification for this product.
    IETF P802.1Q Affected: D1.0 , ≤ D1.0 (custom)
    		Create a notification for this product.
    Date Public
    2022-09-27 00:00
    Credits
    Etienne Champetier (@champtar) <champetier.etienne@gmail.com>
    Show details on NVD website
    To clipboard 

    {
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-04T19:12:25.432Z",
          "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://standards.ieee.org/ieee/802.1Q/10323/"
          },
          {
            "name": "20220927 Vulnerabilities in Layer 2 Network Security Controls Affecting Cisco Products: September 2022",
            "tags": [
              "vendor-advisory",
              "x_transferred"
            ],
            "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-VU855201-J3z8CKTX"
          },
          {
            "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-2021-27853",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-05-21T15:26:49.324466Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-05-21T15:27:39.621Z",
          "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",
          "vendor": "IETF",
          "versions": [
            {
              "lessThanOrEqual": "08",
              "status": "affected",
              "version": "08",
              "versionType": "custom"
            }
          ]
        },
        {
          "product": "P802.1Q",
          "vendor": "IETF",
          "versions": [
            {
              "lessThanOrEqual": "D1.0",
              "status": "affected",
              "version": "D1.0",
              "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 or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers."
        }
      ],
      "problemTypes": [
        {
          "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://standards.ieee.org/ieee/802.1Q/10323/"
        },
        {
          "name": "20220927 Vulnerabilities in Layer 2 Network Security Controls Affecting Cisco Products: September 2022",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-VU855201-J3z8CKTX"
        },
        {
          "url": "https://kb.cert.org/vuls/id/855201"
        },
        {
          "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "37e5125f-f79b-445b-8fad-9564f167944b",
    "assignerShortName": "certcc",
    "cveId": "CVE-2021-27853",
    "datePublished": "2022-09-27T17:55:09.203Z",
    "dateReserved": "2021-03-01T00:00:00.000Z",
    "dateUpdated": "2025-11-04T19:12:25.432Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

    CVE-2021-27853 (GCVE-0-2021-27853)

    Vulnerability from nvd – Published: 2022-09-27 17:55 – Updated: 2025-11-04 19:12
    VLAI
    Title
    L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers
    Summary
    Layer 2 network filtering capabilities such as IPv6 RA guard or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers.
    Severity
    4.7 (Medium)
    CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
    SSVC
    Exploitation: none Automatable: no Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-290 - Authentication Bypass by Spoofing
    Assigner
    References
    Impacted products
    Vendor Product Version
    IEEE 802.2 Affected: 802.2h-1997 , ≤ 802.2h-1997 (custom)
    		Create a notification for this product.
    IETF draft-ietf-v6ops-ra-guard Affected: 08 , ≤ 08 (custom)
    		Create a notification for this product.
    IETF P802.1Q Affected: D1.0 , ≤ D1.0 (custom)
    		Create a notification for this product.
    Date Public
    2022-09-27 00:00
    Credits
    Etienne Champetier (@champtar) <champetier.etienne@gmail.com>
    Show details on NVD website
    To clipboard 

    {
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2025-11-04T19:12:25.432Z",
          "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://standards.ieee.org/ieee/802.1Q/10323/"
          },
          {
            "name": "20220927 Vulnerabilities in Layer 2 Network Security Controls Affecting Cisco Products: September 2022",
            "tags": [
              "vendor-advisory",
              "x_transferred"
            ],
            "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-VU855201-J3z8CKTX"
          },
          {
            "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-2021-27853",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-05-21T15:26:49.324466Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-05-21T15:27:39.621Z",
          "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",
          "vendor": "IETF",
          "versions": [
            {
              "lessThanOrEqual": "08",
              "status": "affected",
              "version": "08",
              "versionType": "custom"
            }
          ]
        },
        {
          "product": "P802.1Q",
          "vendor": "IETF",
          "versions": [
            {
              "lessThanOrEqual": "D1.0",
              "status": "affected",
              "version": "D1.0",
              "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 or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers."
        }
      ],
      "problemTypes": [
        {
          "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://standards.ieee.org/ieee/802.1Q/10323/"
        },
        {
          "name": "20220927 Vulnerabilities in Layer 2 Network Security Controls Affecting Cisco Products: September 2022",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-VU855201-J3z8CKTX"
        },
        {
          "url": "https://kb.cert.org/vuls/id/855201"
        },
        {
          "url": "https://blog.champtar.fr/VLAN0_LLC_SNAP/"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "L2 network filtering can be bypassed using stacked VLAN0 and LLC/SNAP headers"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "37e5125f-f79b-445b-8fad-9564f167944b",
    "assignerShortName": "certcc",
    "cveId": "CVE-2021-27853",
    "datePublished": "2022-09-27T17:55:09.203Z",
    "dateReserved": "2021-03-01T00:00:00.000Z",
    "dateUpdated": "2025-11-04T19:12:25.432Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}