FKIE_CVE-2021-34420

Vulnerability from fkie_nvd - Published: 2021-11-11 23:15 - Updated: 2026-06-17 03:55
Severity
4.7 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N
7.4 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N
Summary
The Zoom Client for Meetings for Windows installer before version 5.5.4 does not properly verify the signature of files with .msi, .ps1, and .bat extensions. This could lead to a malicious actor installing malicious software on a customer’s computer.
References
security@zoom.ushttps://explore.zoom.us/en/trust/security/security-bulletinVendor Advisory
security@zoom.ushttps://medium.com/manomano-tech/a-red-team-operation-leveraging-a-zero-day-vulnerability-in-zoom-80f57fb0822eThird Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://explore.zoom.us/en/trust/security/security-bulletinVendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://medium.com/manomano-tech/a-red-team-operation-leveraging-a-zero-day-vulnerability-in-zoom-80f57fb0822eThird Party Advisory
Impacted products
Vendor Product Version
zoom zoom_client_for_meetings *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Zoom Client for Meetings for Windows",
          "vendor": "Zoom Video Communications Inc",
          "versions": [
            {
              "lessThan": "5.5.4",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "security@zoom.us"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:zoom:zoom_client_for_meetings:*:*:*:*:*:windows:*:*",
              "matchCriteriaId": "CB0A66B6-7584-4017-87B5-D1937E16C7CB",
              "versionEndExcluding": "5.4.4",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Zoom Client for Meetings for Windows installer before version 5.5.4 does not properly verify the signature of files with .msi, .ps1, and .bat extensions. This could lead to a malicious actor installing malicious software on a customer\u2019s computer."
    },
    {
      "lang": "es",
      "value": "El instalador de Zoom Client for Meetings para Windows anterior a la versi\u00f3n 5.5.4 no verifica correctamente la firma de los archivos con extensiones .msi, .ps1 y .bat. Esto podr\u00eda dar lugar a que un actor malintencionado instalara software malicioso en el ordenador de un cliente"
    }
  ],
  "id": "CVE-2021-34420",
  "lastModified": "2026-06-17T03:55:49.360",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 4.3,
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.7,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4,
        "source": "security@zoom.us",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 4.0,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-11-11T23:15:09.827",
  "references": [
    {
      "source": "security@zoom.us",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://explore.zoom.us/en/trust/security/security-bulletin"
    },
    {
      "source": "security@zoom.us",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://medium.com/manomano-tech/a-red-team-operation-leveraging-a-zero-day-vulnerability-in-zoom-80f57fb0822e"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://explore.zoom.us/en/trust/security/security-bulletin"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://medium.com/manomano-tech/a-red-team-operation-leveraging-a-zero-day-vulnerability-in-zoom-80f57fb0822e"
    }
  ],
  "sourceIdentifier": "security@zoom.us",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-347"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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