{
    "id": "CVE-2023-44487",
    "published": "2023-10-10 14:15:10",
    "last_modified": "2026-08-11 19:37:30",
    "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-400",
    "description": "The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.",
    "epss_score": "0.99999",
    "epss_percentile": "0.99998",
    "kev": 1,
    "kev_due": "2023-10-31",
    "has_exploit": 1,
    "updated_at": "2026-09-26 18:32:46",
    "priority": {
        "rank": 1,
        "label": "Patch first",
        "why": "On CISA KEV — known exploited in the wild, due 2023-10-31."
    },
    "products": [
        {
            "vendor": "caddyserver",
            "product": "caddy"
        },
        {
            "vendor": "eclipse",
            "product": "jetty"
        },
        {
            "vendor": "envoyproxy",
            "product": "envoy"
        },
        {
            "vendor": "f5",
            "product": "big-ip_access_policy_manager"
        },
        {
            "vendor": "f5",
            "product": "big-ip_advanced_firewall_manager"
        },
        {
            "vendor": "f5",
            "product": "big-ip_advanced_web_application_firewall"
        },
        {
            "vendor": "f5",
            "product": "big-ip_analytics"
        },
        {
            "vendor": "f5",
            "product": "big-ip_application_acceleration_manager"
        },
        {
            "vendor": "f5",
            "product": "big-ip_application_security_manager"
        },
        {
            "vendor": "f5",
            "product": "big-ip_application_visibility_and_reporting"
        },
        {
            "vendor": "f5",
            "product": "big-ip_carrier-grade_nat"
        },
        {
            "vendor": "f5",
            "product": "big-ip_ddos_hybrid_defender"
        },
        {
            "vendor": "f5",
            "product": "big-ip_domain_name_system"
        },
        {
            "vendor": "f5",
            "product": "big-ip_fraud_protection_service"
        },
        {
            "vendor": "f5",
            "product": "big-ip_global_traffic_manager"
        },
        {
            "vendor": "f5",
            "product": "big-ip_link_controller"
        },
        {
            "vendor": "f5",
            "product": "big-ip_local_traffic_manager"
        },
        {
            "vendor": "f5",
            "product": "big-ip_next"
        },
        {
            "vendor": "f5",
            "product": "big-ip_next_service_proxy_for_kubernetes"
        },
        {
            "vendor": "f5",
            "product": "big-ip_policy_enforcement_manager"
        },
        {
            "vendor": "f5",
            "product": "big-ip_ssl_orchestrator"
        },
        {
            "vendor": "f5",
            "product": "big-ip_webaccelerator"
        },
        {
            "vendor": "f5",
            "product": "big-ip_websafe"
        },
        {
            "vendor": "golang",
            "product": "go"
        },
        {
            "vendor": "golang",
            "product": "http2"
        },
        {
            "vendor": "golang",
            "product": "networking"
        },
        {
            "vendor": "ietf",
            "product": "http"
        },
        {
            "vendor": "netty",
            "product": "netty"
        },
        {
            "vendor": "nghttp2",
            "product": "nghttp2"
        },
        {
            "vendor": "siemens",
            "product": "ruggedcom_ape1808"
        },
        {
            "vendor": "siemens",
            "product": "ruggedcom_ape1808_firmware"
        },
        {
            "vendor": "siemens",
            "product": "simatic_s7-1500_cpu_1518-4_pn\\/dp"
        },
        {
            "vendor": "siemens",
            "product": "simatic_s7-1500_cpu_1518-4_pn\\/dp_mfp_firmware"
        },
        {
            "vendor": "siemens",
            "product": "simatic_s7-1500_cpu_1518f-4_pn\\/dp_mfp"
        },
        {
            "vendor": "siemens",
            "product": "simatic_s7-1500_cpu_1518f-4_pn\\/dp_mfp_firmware"
        },
        {
            "vendor": "siemens",
            "product": "sinec_ins"
        },
        {
            "vendor": "siemens",
            "product": "sinec_nms"
        },
        {
            "vendor": "siemens",
            "product": "siplus_s7-1500_cpu_1518-4_pn\\/dp_mfp"
        },
        {
            "vendor": "siemens",
            "product": "siplus_s7-1500_cpu_1518-4_pn\\/dp_mfp_firmware"
        },
        {
            "vendor": "siemens",
            "product": "st7_scadaconnect"
        }
    ],
    "kev_detail": {
        "cve_id": "CVE-2023-44487",
        "date_added": "2023-10-10",
        "due_date": "2023-10-31",
        "vendor": "IETF",
        "product": "HTTP/2",
        "name": "HTTP/2 Rapid Reset Attack Vulnerability",
        "ransomware": 0
    },
    "exploits": [
        {
            "source": "exploit-db",
            "ref_id": "52426",
            "title": "HTTP/2 2.0 - Denial Of Service (DOS)",
            "date": "2025-09-16",
            "url": "https://www.exploit-db.com/exploits/52426"
        }
    ],
    "refs_list": [
        "http://www.openwall.com/lists/oss-security/2023/10/10/6",
        "http://www.openwall.com/lists/oss-security/2023/10/10/7",
        "http://www.openwall.com/lists/oss-security/2023/10/13/4",
        "http://www.openwall.com/lists/oss-security/2023/10/13/9",
        "http://www.openwall.com/lists/oss-security/2023/10/18/4",
        "http://www.openwall.com/lists/oss-security/2023/10/18/8",
        "http://www.openwall.com/lists/oss-security/2023/10/19/6",
        "http://www.openwall.com/lists/oss-security/2023/10/20/8",
        "https://access.redhat.com/security/cve/cve-2023-44487",
        "https://arstechnica.com/security/2023/10/how-ddosers-used-the-http-2-protocol-to-deliver-attacks-of-unprecedented-size/",
        "https://aws.amazon.com/security/security-bulletins/AWS-2023-011/",
        "https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/",
        "https://blog.cloudflare.com/zero-day-rapid-reset-http2-record-breaking-ddos-attack/",
        "https://blog.litespeedtech.com/2023/10/11/rapid-reset-http-2-vulnerablilty/",
        "https://blog.qualys.com/vulnerabilities-threat-research/2023/10/10/cve-2023-44487-http-2-rapid-reset-attack",
        "https://blog.vespa.ai/cve-2023-44487/",
        "https://bugzilla.proxmox.com/show_bug.cgi?id=4988",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2242803",
        "https://bugzilla.suse.com/show_bug.cgi?id=1216123",
        "https://cgit.freebsd.org/ports/commit/?id=c64c329c2c1752f46b73e3e6ce9f4329be6629f9",
        "https://cloud.google.com/blog/products/identity-security/google-cloud-mitigated-largest-ddos-attack-peaking-above-398-million-rps/",
        "https://cloud.google.com/blog/products/identity-security/how-it-works-the-novel-http2-rapid-reset-ddos-attack",
        "https://community.traefik.io/t/is-traefik-vulnerable-to-cve-2023-44487/20125",
        "https://discuss.hashicorp.com/t/hcsec-2023-32-vault-consul-and-boundary-affected-by-http-2-rapid-reset-denial-of-service-vulnerability-cve-2023-44487/59715",
        "https://edg.io/lp/blog/resets-leaks-ddos-and-the-tale-of-a-hidden-cve"
    ]
}