FKIE_CVE-2021-40120

Vulnerability from fkie_nvd - Published: 2021-11-04 16:15 - Updated: 2026-06-17 04:06
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
7.2 (High) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Summary
A vulnerability in the web-based management interface of certain Cisco Small Business RV Series Routers could allow an authenticated, remote attacker with administrative privileges to inject arbitrary commands into the underlying operating system and execute them using root-level privileges. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending malicious input to a specific field in the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying Linux operating system as a user with root-level privileges.
References
psirt@cisco.comhttps://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbrv-cmdinjection-Z5cWFdKVendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbrv-cmdinjection-Z5cWFdKVendor Advisory
Impacted products
Vendor Product Version
cisco ios_xr 4.2.3.06
cisco rv016 -
cisco rv042 -
cisco rv042g -
cisco rv082 -
cisco rv320 -
cisco rv325 -
cisco application_extension_platform 1.5.1.13
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Cisco Small Business RV Series Router Firmware",
          "vendor": "Cisco",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "psirt@cisco.com"
    }
  ],
  "configurations": [
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            }
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    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in the web-based management interface of certain Cisco Small Business RV Series Routers could allow an authenticated, remote attacker with administrative privileges to inject arbitrary commands into the underlying operating system and execute them using root-level privileges. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending malicious input to a specific field in the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying Linux operating system as a user with root-level privileges."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en la interfaz de administraci\u00f3n basada en la web de algunos routers de la serie RV de Cisco Small Business podr\u00eda permitir a un atacante remoto autenticado con privilegios administrativos inyectar comandos arbitrarios en el sistema operativo subyacente y ejecutarlos usando privilegios de nivel de root. Esta vulnerabilidad es debido a que no se comprueba suficientemente la entrada proporcionada por el usuario. Un atacante podr\u00eda explotar esta vulnerabilidad mediante el env\u00edo de una entrada maliciosa a un campo espec\u00edfico de la interfaz de administraci\u00f3n basada en la web de un dispositivo afectado. Una explotaci\u00f3n con \u00e9xito podr\u00eda permitir al atacante ejecutar comandos arbitrarios en el sistema operativo Linux subyacente como un usuario con privilegios de nivel de root"
    }
  ],
  "id": "CVE-2021-40120",
  "lastModified": "2026-06-17T04:06:33.550",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "HIGH",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "COMPLETE",
          "baseScore": 9.0,
          "confidentialityImpact": "COMPLETE",
          "integrityImpact": "COMPLETE",
          "vectorString": "AV:N/AC:L/Au:S/C:C/I:C/A:C",
          "version": "2.0"
        },
        "exploitabilityScore": 8.0,
        "impactScore": 10.0,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
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        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.2,
        "impactScore": 5.2,
        "source": "psirt@cisco.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.2,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
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        "impactScore": 5.9,
        "source": "nvd@nist.gov",
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    "ssvcV203": [
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        "ssvcData": {
          "id": "CVE-2021-40120",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-11-07T21:42:44.419677Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2021-11-04T16:15:09.430",
  "references": [
    {
      "source": "psirt@cisco.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbrv-cmdinjection-Z5cWFdK"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
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  "sourceIdentifier": "psirt@cisco.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
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          "value": "CWE-20"
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      ],
      "source": "psirt@cisco.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-78"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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