{
    "id": "CVE-2021-42697",
    "published": "2021-11-02 22:15:08",
    "last_modified": "2026-06-17 04:09:58",
    "cvss_score": "7.5",
    "cvss_severity": "HIGH",
    "cvss_version": "3.1",
    "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
    "cwe": "CWE-674",
    "description": "Akka HTTP 10.1.x before 10.1.15 and 10.2.x before 10.2.7 can encounter stack exhaustion while parsing HTTP headers, which allows a remote attacker to conduct a Denial of Service attack by sending a User-Agent header with deeply nested comments.",
    "epss_score": "0.36139",
    "epss_percentile": "0.98429",
    "kev": 0,
    "kev_due": null,
    "has_exploit": 1,
    "updated_at": "2026-09-28 18:17:30",
    "priority": {
        "rank": 2,
        "label": "Patch early",
        "why": "A public exploit exists."
    },
    "products": [
        {
            "vendor": "akka",
            "product": "http_server"
        }
    ],
    "kev_detail": null,
    "exploits": [
        {
            "source": "exploit-db",
            "ref_id": "50892",
            "title": "Akka HTTP 10.1.14 - Denial of Service",
            "date": "2022-05-11",
            "url": "https://www.exploit-db.com/exploits/50892"
        }
    ],
    "refs_list": [
        "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html",
        "https://akka.io/blog/",
        "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released",
        "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released",
        "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html",
        "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html",
        "https://akka.io/blog/",
        "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released",
        "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released",
        "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html"
    ]
}