CVE-2021-1268
A vulnerability in the IPv6 protocol handling of the management interfaces of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause an IPv6 flood on the management interface network of an affected device. The vulnerability exists because the software incorrectly forwards IPv6 packets that have an IPv6 node-local multicast group address destination and are received on the management interfaces.
Leer descripción completaMostrar menos
An attacker could exploit this vulnerability by connecting to the same network as the management interfaces and injecting IPv6 packets that have an IPv6 node-local multicast group address destination. A successful exploit could allow the attacker to cause an IPv6 flood on the corresponding network. Depending on the number of Cisco IOS XR Software nodes on that network segment, exploitation could cause excessive network traffic, resulting in network degradation or a denial of service (DoS) condition.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.50%
- Percentil entre todas las CVEs puntuadas: 41
- Fecha de la puntuación: 7/10/2026
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)
CWE
- CWE-1076
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-1268",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2021-1268",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2024-11-08T20:49:57.430099Z"
}
}
],
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 3.3,
"accessVector": "ADJACENT_NETWORK",
"vectorString": "AV:A/AC:L/Au:N/C:N/I:N/A:P",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "LOW",
"obtainAllPrivilege": false,
"exploitabilityScore": 6.5,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "psirt@cisco.com",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 7.4,
"attackVector": "ADJACENT_NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 4,
"exploitabilityScore": 2.8
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 6.5,
"attackVector": "ADJACENT_NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 2.8
}
]
},
"affected": [
{
"source": "psirt@cisco.com",
"affectedData": [
{
"vendor": "Cisco",
"product": "Cisco IOS XR Software",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2021-02-04T17:15:14.967",
"references": [
{
"url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xripv6-spJem78K",
"tags": [
"Vendor Advisory"
],
"source": "psirt@cisco.com"
},
{
"url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xripv6-spJem78K",
"tags": [
"Vendor Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "psirt@cisco.com",
"description": [
{
"lang": "en",
"value": "CWE-1076"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability in the IPv6 protocol handling of the management interfaces of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause an IPv6 flood on the management interface network of an affected device. The vulnerability exists because the software incorrectly forwards IPv6 packets that have an IPv6 node-local multicast group address destination and are received on the management interfaces. An attacker could exploit this vulnerability by connecting to the same network as the management interfaces and injecting IPv6 packets that have an IPv6 node-local multicast group address destination. A successful exploit could allow the attacker to cause an IPv6 flood on the corresponding network. Depending on the number of Cisco IOS XR Software nodes on that network segment, exploitation could cause excessive network traffic, resulting in network degradation or a denial of service (DoS) condition."
},
{
"lang": "es",
"value": "Una vulnerabilidad en el manejo del protocolo IPv6 de las interfaces de administración del Software Cisco IOS XR, podría permitir a un atacante adyacente no autenticado causar una inundación de IPv6 en la red de la interfaz de administración de un dispositivo afectado. La vulnerabilidad se presenta porque el software reenvía incorrectamente paquetes IPv6 que contienen un destino de dirección de grupo de multidifusión local de nodo IPv6 y son recibidos en las interfaces de administración. Un atacante podría explotar esta vulnerabilidad al conectarse a la misma red que las interfaces de administración e inyectando paquetes IPv6 que contienen un destino de dirección de grupo de multidifusión local de nodo IPv6. Una explotación con éxito podría permitir al atacante causar una inundación de IPv6 en la red correspondiente. Dependiendo de la cantidad de nodos del Software Cisco IOS XR, en ese segmento de red, la explotación podría causar un tráfico de red excesivo, resultando en una degradación de la red o una condición de denegación de servicio (DoS)"
}
],
"lastModified": "2026-06-17T03:31:22.420",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "51C3061D-B020-4F38-A0DE-67DDAAFC269E",
"versionEndExcluding": "6.7.3"
},
{
"criteria": "cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "010C84AB-7633-4A88-8938-7158EFC1E01C",
"versionEndExcluding": "7.1.3",
"versionStartIncluding": "7.1.0"
},
{
"criteria": "cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "2EA0CDB4-13C5-48BC-B3F5-36F8E2BD8DA1",
"versionEndExcluding": "7.2.2",
"versionStartIncluding": "7.2.0"
},
{
"criteria": "cpe:2.3:o:cisco:ios_xr:7.3.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "323C8DEE-3009-4D8D-A63F-873D2432F3A4"
}
],
"operator": "OR"
},
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:h:cisco:ncs_1001:-:*:*:*:*:*:*:*",
"vulnerable": false,
"matchCriteriaId": "0F6E0FBE-70B7-413C-8943-39BEFE050298"
},
{
"criteria": "cpe:2.3:h:cisco:ncs_1002:-:*:*:*:*:*:*:*",
"vulnerable": false,
"matchCriteriaId": "37AE5FB0-D9A6-4EBE-9F7F-243299AE918B"
}
],
"operator": "OR"
}
],
"operator": "AND"
}
],
"sourceIdentifier": "psirt@cisco.com"
}