CVE-2021-34716
A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system as the root user. This vulnerability is due to incorrect handling of certain crafted software images that are uploaded to the affected device. An attacker could exploit this vulnerability by authenticating to the system as an administrative user and then uploading specific crafted software images to the affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system as the root user.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 2.40%
- Percentil entre todas las CVEs puntuadas: 83
- 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 (2)
CWE
- CWE-460
- CWE-755
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-34716",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2021-34716",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2024-11-07T21:43:27.670741Z"
}
}
],
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 9,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:L/Au:S/C:C/I:C/A:C",
"authentication": "SINGLE",
"integrityImpact": "COMPLETE",
"accessComplexity": "LOW",
"availabilityImpact": "COMPLETE",
"confidentialityImpact": "COMPLETE"
},
"acInsufInfo": false,
"impactScore": 10,
"baseSeverity": "HIGH",
"obtainAllPrivilege": false,
"exploitabilityScore": 8,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "psirt@cisco.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 6.7,
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "LOW",
"privilegesRequired": "HIGH",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.5,
"exploitabilityScore": 1.2
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.2,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "HIGH",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.2
}
]
},
"affected": [
{
"source": "psirt@cisco.com",
"affectedData": [
{
"vendor": "Cisco",
"product": "Cisco TelePresence Video Communication Server (VCS) Expressway",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2021-08-18T20:15:07.300",
"references": [
{
"url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewrce-QPynNCjh",
"tags": [
"Patch",
"Vendor Advisory"
],
"source": "psirt@cisco.com"
},
{
"url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewrce-QPynNCjh",
"tags": [
"Patch",
"Vendor Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "psirt@cisco.com",
"description": [
{
"lang": "en",
"value": "CWE-460"
}
]
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-755"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system as the root user. This vulnerability is due to incorrect handling of certain crafted software images that are uploaded to the affected device. An attacker could exploit this vulnerability by authenticating to the system as an administrative user and then uploading specific crafted software images to the affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system as the root user."
},
{
"lang": "es",
"value": "Una vulnerabilidad en la interfaz de administración basada en la web de la serie Expressway de Cisco y Cisco TelePresence Video Communication Server (VCS), podría permitir a un atacante autenticado remoto ejecutar código arbitrario en el sistema operativo subyacente como usuario root. Esta vulnerabilidad es debido al manejo incorrecto de determinadas imágenes de software diseñadas que son cargados en el dispositivo afectado. Un atacante podría explotar esta vulnerabilidad al autenticarse en el sistema como un usuario administrativo y luego cargando imágenes de software específicamente diseñadas en el dispositivo afectado. Una explotación con éxito podría permitir al atacante ejecutar código arbitrario en el sistema operativo subyacente como usuario root."
}
],
"lastModified": "2026-06-17T03:56:24.937",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:cisco:expressway:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "166EC2E2-2F58-4E14-B7D5-199D6F2AF2C6",
"versionEndExcluding": "x14.1",
"versionStartIncluding": "x8.6.0"
},
{
"criteria": "cpe:2.3:a:cisco:telepresence_video_communication_server:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C5D50DF5-EAE1-4923-AC00-67AA11D3C162",
"versionEndIncluding": "x14.0.3",
"versionStartIncluding": "x8.6"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "psirt@cisco.com"
}