{
    "id": "CVE-2021-1879",
    "published": "2021-04-02 19:15:20",
    "last_modified": "2026-06-17 03:32:42",
    "cvss_score": "6.1",
    "cvss_severity": "MEDIUM",
    "cvss_version": "3.1",
    "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
    "cwe": "CWE-79",
    "description": "This issue was addressed by improved management of object lifetimes. This issue is fixed in iOS 12.5.2, iOS 14.4.2 and iPadOS 14.4.2, watchOS 7.3.3. Processing maliciously crafted web content may lead to universal cross site scripting. Apple is aware of a report that this issue may have been actively exploited..",
    "epss_score": "0.07082",
    "epss_percentile": "0.94003",
    "kev": 1,
    "kev_due": "2021-11-17",
    "has_exploit": 0,
    "updated_at": "2026-09-26 18:27:19",
    "priority": {
        "rank": 1,
        "label": "Patch first",
        "why": "On CISA KEV — known exploited in the wild, due 2021-11-17."
    },
    "products": [
        {
            "vendor": "apple",
            "product": "ipados"
        },
        {
            "vendor": "apple",
            "product": "iphone_os"
        },
        {
            "vendor": "apple",
            "product": "watchos"
        }
    ],
    "kev_detail": {
        "cve_id": "CVE-2021-1879",
        "date_added": "2021-11-03",
        "due_date": "2021-11-17",
        "vendor": "Apple",
        "product": "iOS, iPadOS, and watchOS",
        "name": "Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS) Vulnerability",
        "ransomware": 0
    },
    "exploits": [],
    "refs_list": [
        "https://support.apple.com/en-us/HT212256",
        "https://support.apple.com/en-us/HT212257",
        "https://support.apple.com/en-us/HT212258",
        "https://support.apple.com/en-us/HT212256",
        "https://support.apple.com/en-us/HT212257",
        "https://support.apple.com/en-us/HT212258",
        "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-1879"
    ]
}