uscis.f5.si is a disposable email domain

uscis.f5.si is a disposable temp email domain from kuku.lu that provides throwaway email addresses and should be blocked. These temporary addresses are frequently exploited to bypass verification systems and create fake accounts.

Raw API JSON response:

{
    "valid": true,
    "block": true,
    "domain": "uscis.f5.si",
    "base_domain": "uscis.f5.si",
    "text": "Disposable \/ temporary domain",
    "reason": "Disposable",
    "risk": 91,
    "is_disposable": true,
    "is_email_forwarder": false,
    "is_public_free": false,
    "is_public_premium": false,
    "is_business_provider": false,
    "is_isp_email": false,
    "is_email_api": false,
    "is_web_hosting_email": false,
    "is_self_hosted": false,
    "is_parked": false,
    "is_role_based_email": false,
    "mx_host": "recv5.erinn.biz",
    "mx_ip": "160.251.76.226",
    "mx_info": "Using MX pointer vps49.erinn.biz from DNS with priority: 10",
    "mx_fallback": false,
    "mx_hosts": [
        "recv5.erinn.biz",
        "recv7.erinn.biz",
        "recv2.erinn.biz",
        "recv4.erinn.biz",
        "recv3.erinn.biz",
        "recv6.erinn.biz"
    ],
    "mx_ips": [
        "160.251.76.226",
        "133.130.89.189",
        "133.130.97.104",
        "118.27.118.63",
        "160.251.83.161",
        "133.130.99.7"
    ],
    "mx_priorities": {
        "recv2.erinn.biz": 10,
        "recv3.erinn.biz": 10,
        "recv4.erinn.biz": 10,
        "recv5.erinn.biz": 10,
        "recv6.erinn.biz": 10,
        "recv7.erinn.biz": 10
    },
    "email_provider": null,
    "disposable_provider": "kuku.lu",
    "possible_typo": [],
    "domain_age_days": 4667,
    "domain_created_at": "2013-07-03T00:00:00+00:00",
    "block_status_changed_at": "2021-03-15T15:51:12+00:00"
}