CVE-2021-34727

Estado: ModificadaCrítica (9.8)—
A vulnerability in the vDaemon process in Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected device. This vulnerability is due to insufficient bounds checking when an affected device processes traffic. An attacker could exploit this vulnerability by sending crafted traffic to the device. A successful exploit could allow the attacker to cause a buffer overflow and possibly execute arbitrary commands with root-level privileges, or cause the device to reload, which could result in a denial of service condition.
CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8
Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 2.63%
Percentil entre todas las CVEs puntuadas: 85
Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)

Cisco — IOS XE Sd-wan
CWE

CWE-120
CWE-120
Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2021-34727",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-34727",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2024-11-07T21:55:54.920129Z"
        }
      }
    ],
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 10,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C",
          "authentication": "NONE",
          "integrityImpact": "COMPLETE",
          "accessComplexity": "LOW",
          "availabilityImpact": "COMPLETE",
          "confidentialityImpact": "COMPLETE"
        },
        "acInsufInfo": false,
        "impactScore": 10,
        "baseSeverity": "HIGH",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "psirt@cisco.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 9.8,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 3.9
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 9.8,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "psirt@cisco.com",
      "affectedData": [
        {
          "vendor": "Cisco",
          "product": "Cisco IOS XE SD-WAN Software",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ]
    }
  ],
  "published": "2021-09-23T03:15:19.500",
  "references": [
    {
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxesdwan-rbuffover-vE2OB6tp",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "psirt@cisco.com"
    },
    {
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxesdwan-rbuffover-vE2OB6tp",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "psirt@cisco.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-120"
        }
      ]
    },
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-120"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in the vDaemon process in Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected device. This vulnerability is due to insufficient bounds checking when an affected device processes traffic. An attacker could exploit this vulnerability by sending crafted traffic to the device. A successful exploit could allow the attacker to cause a buffer overflow and possibly execute arbitrary commands with root-level privileges, or cause the device to reload, which could result in a denial of service condition."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en el proceso vDaemon de Cisco IOS XE SD-WAN Software podría permitir a un atacante remoto no autenticado causar un desbordamiento del búfer en un dispositivo afectado. Esta vulnerabilidad es debido a una comprobación insuficiente de los límites cuando un dispositivo afectado procesa el tráfico. Un atacante podría explotar esta vulnerabilidad mediante el envío de tráfico diseñado al dispositivo. Una explotación con éxito podría permitir al atacante causar un desbordamiento del búfer y posiblemente ejecutar comandos arbitrarios con privilegios de nivel de root, o causar la recarga del dispositivo, que podría resultar en una condición de denegación de servicio"
    }
  ],
  "lastModified": "2026-06-17T03:56:26.310",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:cisco:ios_xe_sd-wan:-:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "16266B9E-E613-45FA-A02B-51EED8BEFCC9"
            }
          ],
          "operator": "OR"
        },
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:h:cisco:1000_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "F4856E07-B3C2-4674-9584-866F6AF643B2"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1100-4g\\/6g_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "A6F668B9-2C1D-4306-8286-35E67D0F67C7"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1100-4p_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "A2D2305B-B69E-4F74-A44E-07B3205CE9F7"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1100-8p_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "26DD41B3-1D1D-44D3-BA8E-5A66AFEE77E6"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1100_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "1952B64C-4AE0-4CCB-86C5-8D1FF6A12822"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1101-4p_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "5AAD4397-6DCF-493A-BD61-3A890F6F3AB2"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1101_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "5EB8A757-7888-4AC2-BE44-B89DB83C6C77"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1109-2p_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "3F2F0A8E-97F6-41AC-BE67-4B2D60F9D36B"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1109-4p_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "BB9229F3-7BCE-46C4-9879-D57B5BAAE44E"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1109_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "B80890A8-E3D3-462C-B125-9E9BC6525B02"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1111x-8p_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "A5A606FE-E6F1-43F9-B1CD-D9DF35FC3573"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1111x_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "0547E196-5991-4C33-823A-342542E9DFD3"
            },
            {
              "criteria": "cpe:2.3:h:cisco:111x_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "802CBFC1-8A2F-4BF7-A1D3-00622C33BE16"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1120_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "7AFE0FC1-EEBC-42F0-88B0-4AF5B76DDD97"
            },
            {
              "criteria": "cpe:2.3:h:cisco:1160_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "D916389F-54DB-44CB-91DD-7CE3C7059350"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4000_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "CE82335E-ECEC-47BD-BC4A-5FDEA08D1A18"
            },
            {
              "criteria": "cpe:2.3:h:cisco:422_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "03A273EE-41C1-41E9-9002-46F83FC6533F"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4221_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "6C8AED7C-DDA3-4C29-BB95-6518C02C551A"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "9421DBEF-AE42-4234-B49F-FCC34B804D7F"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "5419CB9F-241F-4431-914F-2659BE27BEA5"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "7DE02DBE-EAD5-4F37-8AB7-DF46A605A0E2"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "5720462A-BE6B-4E84-A1A1-01E80BBA86AD"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4451-x_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "818CEFA6-208C-43C3-8E43-474A93ADCF21"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4451_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "82225D40-537F-41D2-B1C4-1B7D06466B06"
            },
            {
              "criteria": "cpe:2.3:h:cisco:4461_integrated_services_router:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "E8B60888-6E2B-494E-AC65-83337661EE7D"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1000:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "91209C16-A620-44A0-9134-8AA456343F29"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1000-esp100:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "3C5C1005-0C12-4EDA-BC4A-B52201C4F516"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1000-x:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "FE2182E7-C813-4966-A36C-E648A9344299"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1000_series:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "76B7C13F-46C5-460A-A6C9-3837A28A0CE2"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1000_series_route_processor_\\(rp2\\):-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "C02F9303-F9DF-4166-AB4B-8C26B9FAD109"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1000_series_route_processor_\\(rp3\\):-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "372CB4D6-BB22-4521-9C18-C0A663717168"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1001:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "ED7C321E-F083-4AB6-96A0-D6358980441E"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1001-hx:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "7594E307-AC80-41EC-AE94-07E664A7D701"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1001-hx_r:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "33208B25-0CBB-4E31-A892-60B7B5625155"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1001-x:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "09C913FF-63D5-43FB-8B39-598EF436BA5A"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1001-x_r:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "241EEBD9-76E4-4AE6-96B8-1C1ACD834F17"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1002:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "E4376E56-A21C-4642-A85D-439C8E21CD7F"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1002-hx:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "CD2794BD-C8CE-46EF-9857-1723FCF04E46"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1002-hx_r:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "CC03A84F-C8F2-4225-9A00-8FA35368CD57"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1002-x:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "444F688F-79D0-4F22-B530-7BD520080B8F"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1002-x_r:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "51F2A755-556C-4C5E-8622-96D124319AF7"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1004:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "55DD2272-10C2-43B9-9F13-6DC41DBE179B"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1006:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "7428E0A8-1641-47FB-9CA9-34311DEF660D"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1006-x:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "DE7401B7-094C-46EB-9869-2F0372E8B26B"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1009-x:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "8D8A72FD-D8B0-45B5-8FAD-6D8395BB218A"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1013:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "854D9594-FE84-4E7B-BA21-A3287F2DC302"
            },
            {
              "criteria": "cpe:2.3:h:cisco:asr_1023:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "C81CC6E3-B989-4730-820E-46734E3E608D"
            },
            {
              "criteria": "cpe:2.3:h:cisco:csr_1000v:-:*:*:*:*:*:*:*",
              "vulnerable": false,
              "matchCriteriaId": "BF8B0B49-2C99-410B-B011-5B821C5992FB"
            }
          ],
          "operator": "OR"
        }
      ],
      "operator": "AND"
    }
  ],
  "sourceIdentifier": "psirt@cisco.com"
}