{
  "id": "CVE-2021-30663",
  "url": "https://spydr.io/cve/CVE-2021-30663",
  "published": "2021-09-08T15:15:13.413Z",
  "modified": "2026-06-17T03:50:38.903Z",
  "score": 8.8,
  "severity": "high",
  "cvss_version": "3.1",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
  "score_source": "NVD",
  "epss": 0.03521,
  "epss_percentile": 0.889,
  "exploited": true,
  "kev": {
    "added": "2021-11-03",
    "due": "2021-11-17",
    "action": "Apply updates per vendor instructions.",
    "ransomware": "Unknown",
    "name": "Apple Multiple Products WebKit Integer Overflow Vulnerability",
    "notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-30663"
  },
  "ssvc_exploitation": "active",
  "vendors": [
    "Apple"
  ],
  "products": [
    "Apple macOS"
  ],
  "cwes": [
    "CWE-190"
  ],
  "description": "An integer overflow was addressed with improved input validation. This issue is fixed in iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, Safari 14.1.1, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution.",
  "status": "Analyzed",
  "score_type": "Primary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 8.8,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "https://support.apple.com/en-us/HT212335",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://support.apple.com/en-us/HT212336",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://support.apple.com/en-us/HT212341",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://support.apple.com/en-us/HT212532",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://support.apple.com/en-us/HT212534",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30663",
      "tags": [
        "Third Party Advisory",
        "US Government Resource"
      ]
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2021-30663",
  "covered_in": [],
  "attribution": [
    {
      "source": "NVD",
      "url": "https://nvd.nist.gov",
      "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD."
    },
    {
      "source": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "notice": "Known exploited vulnerabilities from the CISA KEV catalog."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss",
      "notice": "Exploit prediction scores from FIRST EPSS."
    }
  ]
}