{
    "id": "CVE-2017-5637",
    "published": "2017-10-10 01:30:22",
    "last_modified": "2026-06-17 01:20:53",
    "cvss_score": "7.5",
    "cvss_severity": "HIGH",
    "cvss_version": "3.0",
    "cvss_vector": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
    "cwe": "CWE-306",
    "description": "Two four letter word commands \"wchp/wchc\" are CPU intensive and could cause spike of CPU utilization on Apache ZooKeeper server if abused, which leads to the server unable to serve legitimate client requests. Apache ZooKeeper thru version 3.4.9 and 3.5.2 suffer from this issue, fixed in 3.4.10, 3.5.3, and later.",
    "epss_score": "0.73064",
    "epss_percentile": "0.99442",
    "kev": 0,
    "kev_due": null,
    "has_exploit": 1,
    "updated_at": "2026-09-27 18:17:19",
    "priority": {
        "rank": 2,
        "label": "Patch early",
        "why": "A public exploit exists."
    },
    "products": [
        {
            "vendor": "apache",
            "product": "zookeeper"
        },
        {
            "vendor": "debian",
            "product": "debian_linux"
        }
    ],
    "kev_detail": null,
    "exploits": [
        {
            "source": "exploit-db",
            "ref_id": "42294",
            "title": "Zookeeper 3.5.2 Client - Denial of Service",
            "date": "2017-07-02",
            "url": "https://www.exploit-db.com/exploits/42294"
        }
    ],
    "refs_list": [
        "http://www.debian.org/security/2017/dsa-3871",
        "http://www.securityfocus.com/bid/98814",
        "https://access.redhat.com/errata/RHSA-2017:2477",
        "https://access.redhat.com/errata/RHSA-2017:3354",
        "https://access.redhat.com/errata/RHSA-2017:3355",
        "https://issues.apache.org/jira/browse/ZOOKEEPER-2693",
        "https://lists.apache.org/thread.html/053d9ce4d579b02203db18545fee5e33f35f2932885459b74d1e4272%40%3Cissues.activemq.apache.org%3E",
        "https://lists.apache.org/thread.html/58170aeb7a681d462b7fa31cae81110cbb749d2dc83c5736a0bb8370%40%3Cdev.zookeeper.apache.org%3E",
        "https://lists.apache.org/thread.html/bcce5a9c532b386c68dab2f6b3ce8b0cc9b950ec551766e76391caa3%40%3Ccommits.nifi.apache.org%3E",
        "https://lists.apache.org/thread.html/rca37935d661f4689cb4119f1b3b224413b22be161b678e6e6ce0c69b%40%3Ccommits.nifi.apache.org%3E",
        "https://www.oracle.com//security-alerts/cpujul2021.html",
        "https://www.oracle.com/security-alerts/cpujul2020.html",
        "http://www.debian.org/security/2017/dsa-3871",
        "http://www.securityfocus.com/bid/98814",
        "https://access.redhat.com/errata/RHSA-2017:2477",
        "https://access.redhat.com/errata/RHSA-2017:3354",
        "https://access.redhat.com/errata/RHSA-2017:3355",
        "https://issues.apache.org/jira/browse/ZOOKEEPER-2693",
        "https://lists.apache.org/thread.html/053d9ce4d579b02203db18545fee5e33f35f2932885459b74d1e4272%40%3Cissues.activemq.apache.org%3E",
        "https://lists.apache.org/thread.html/58170aeb7a681d462b7fa31cae81110cbb749d2dc83c5736a0bb8370%40%3Cdev.zookeeper.apache.org%3E",
        "https://lists.apache.org/thread.html/bcce5a9c532b386c68dab2f6b3ce8b0cc9b950ec551766e76391caa3%40%3Ccommits.nifi.apache.org%3E",
        "https://lists.apache.org/thread.html/rca37935d661f4689cb4119f1b3b224413b22be161b678e6e6ce0c69b%40%3Ccommits.nifi.apache.org%3E",
        "https://www.oracle.com//security-alerts/cpujul2021.html",
        "https://www.oracle.com/security-alerts/cpujul2020.html"
    ]
}