{
    "id": "CVE-2019-20477",
    "published": "2020-02-19 04:15:10",
    "last_modified": "2026-06-17 02:30:32",
    "cvss_score": "9.8",
    "cvss_severity": "CRITICAL",
    "cvss_version": "3.1",
    "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
    "cwe": "CWE-502",
    "description": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
    "epss_score": "0.05114",
    "epss_percentile": "0.92155",
    "kev": 0,
    "kev_due": null,
    "has_exploit": 0,
    "updated_at": "2026-10-07 18:17:20",
    "priority": {
        "rank": 3,
        "label": "In your normal cycle",
        "why": "Critical by CVSS (9.8), but no sign of active exploitation."
    },
    "products": [
        {
            "vendor": "fedoraproject",
            "product": "fedora"
        },
        {
            "vendor": "pyyaml",
            "product": "pyyaml"
        }
    ],
    "kev_detail": null,
    "exploits": [],
    "refs_list": [
        "https://github.com/yaml/pyyaml/blob/master/CHANGES",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/",
        "https://www.exploit-db.com/download/47655",
        "https://github.com/yaml/pyyaml/blob/master/CHANGES",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/",
        "https://www.exploit-db.com/download/47655"
    ]
}