FKIE_CVE-2021-35033

Vulnerability from fkie_nvd - Published: 2021-11-23 22:15 - Updated: 2026-06-17 03:57
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
A vulnerability in specific versions of Zyxel NBG6818, NBG7815, WSQ20, WSQ50, WSQ60, and WSR30 firmware with pre-configured password management could allow an attacker to obtain root access of the device, if the local attacker dismantles the device and uses a USB-to-UART cable to connect the device, or if the remote assistance feature had been enabled by an authenticated user.
References
security@zyxel.com.twhttps://www.tenable.com/security/research/tra-2022-06Exploit, Third Party Advisory
security@zyxel.com.twhttps://www.zyxel.com/support/Zyxel_security_advisory_for_pre-configured_password_management_vulnerability_of_home_routers_and_WiFi_systems.shtmlVendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.tenable.com/security/research/tra-2022-06Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.zyxel.com/support/Zyxel_security_advisory_for_pre-configured_password_management_vulnerability_of_home_routers_and_WiFi_systems.shtmlVendor Advisory
Impacted products
Vendor Product Version
zyxel nbg6818_firmware *
zyxel nbg6818 -
zyxel nbg7815_firmware *
zyxel nbg7815 -
zyxel wsq20_firmware *
zyxel wsq20 -
zyxel wsq50_firmware *
zyxel wsq50 -
zyxel wsq60_firmware *
zyxel wsq60 -
zyxel wsr30_firmware *
zyxel wsr30 -
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "NBG6818 series firmware",
          "vendor": "Zyxel",
          "versions": [
            {
              "status": "affected",
              "version": "1.00(ABSC.0)C0 through 1.00(ABSC.4)C0"
            }
          ]
        },
        {
          "product": "NBG7815 series firmware",
          "vendor": "Zyxel",
          "versions": [
            {
              "status": "affected",
              "version": "1.00(ABSK.0)C0 through 1.00(ABSK.6)C0"
            }
          ]
        },
        {
          "product": "WSQ20 series firmware",
          "vendor": "Zyxel",
          "versions": [
            {
              "status": "affected",
              "version": "1.00(ABOF.0)C0 through 1.00(ABOF.10)C0"
            }
          ]
        },
        {
          "product": "WSQ50 series firmware",
          "vendor": "Zyxel",
          "versions": [
            {
              "status": "affected",
              "version": "1.00(ABKJ.0)C0 through 2.20(ABKJ.6)C0"
            }
          ]
        },
        {
          "product": "WSQ60 series firmware",
          "vendor": "Zyxel",
          "versions": [
            {
              "status": "affected",
              "version": "1.00(ABND.0)C0 through 2.20(ABND.7)C0"
            }
          ]
        },
        {
          "product": "WSR30 series firmware",
          "vendor": "Zyxel",
          "versions": [
            {
              "status": "affected",
              "version": "1.00(ABMY.0)C0 through 1.00(ABMY.11)C0"
            }
          ]
        }
      ],
      "source": "security@zyxel.com.tw"
    }
  ],
  "configurations": [
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              "versionEndExcluding": "1.00\\(absc.5\\)c0",
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          ],
          "negate": false,
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      ],
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in specific versions of Zyxel NBG6818, NBG7815, WSQ20, WSQ50, WSQ60, and WSR30 firmware with pre-configured password management could allow an attacker to obtain root access of the device, if the local attacker dismantles the device and uses a USB-to-UART cable to connect the device, or if the remote assistance feature had been enabled by an authenticated user."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en versiones espec\u00edficas del firmware de Zyxel NBG6818, NBG7815, WSQ20, WSQ50, WSQ60 y WSR30 con administaci\u00f3n de contrase\u00f1as preconfigurada podr\u00eda permitir a un atacante obtener acceso root del dispositivo, si el atacante local desmonta el dispositivo y usa un cable USB a UART para conectarlo, o si la funcionalidad remote assistance ha sido habilitada por un usuario autenticado"
    }
  ],
  "id": "CVE-2021-35033",
  "lastModified": "2026-06-17T03:57:00.923",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "LOCAL",
          "authentication": "NONE",
          "availabilityImpact": "COMPLETE",
          "baseScore": 6.9,
          "confidentialityImpact": "COMPLETE",
          "integrityImpact": "COMPLETE",
          "vectorString": "AV:L/AC:M/Au:N/C:C/I:C/A:C",
          "version": "2.0"
        },
        "exploitabilityScore": 3.4,
        "impactScore": 10.0,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "security@zyxel.com.tw",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-11-23T22:15:07.623",
  "references": [
    {
      "source": "security@zyxel.com.tw",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://www.tenable.com/security/research/tra-2022-06"
    },
    {
      "source": "security@zyxel.com.tw",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.zyxel.com/support/Zyxel_security_advisory_for_pre-configured_password_management_vulnerability_of_home_routers_and_WiFi_systems.shtml"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      ],
      "url": "https://www.tenable.com/security/research/tra-2022-06"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
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      "url": "https://www.zyxel.com/support/Zyxel_security_advisory_for_pre-configured_password_management_vulnerability_of_home_routers_and_WiFi_systems.shtml"
    }
  ],
  "sourceIdentifier": "security@zyxel.com.tw",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-260"
        }
      ],
      "source": "security@zyxel.com.tw",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-287"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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