{ "id": "CVE-2023-44487", "url": "https://spydr.io/cve/CVE-2023-44487", "published": "2023-10-10T14:15:10.883Z", "modified": "2026-08-11T19:37:30.880Z", "score": 7.5, "severity": "high", "cvss_version": "3.1", "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "score_source": "NVD", "epss": 0.99999, "epss_percentile": 0.99998, "exploited": true, "kev": { "added": "2023-10-10", "due": "2023-10-31", "action": "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.", "ransomware": "Unknown", "name": "HTTP/2 Rapid Reset Attack Vulnerability", "notes": "This vulnerability affects a common open-source component, third-party library, or protocol used by different products. For more information, please see: HTTP/2 Rapid Reset Vulnerability, CVE-2023-44487 | CISA: https://www.cisa.gov/news-events/alerts/2023/10/10/http2-rapid-reset-vulnerability-cve-2023-44487; https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/; https://nvd.nist.gov/vuln/detail/CVE-2023-44487" }, "ssvc_exploitation": "active", "vendors": [ "ietf", "Siemens" ], "products": [ "ietf http", "Siemens RUGGEDCOM APE1808", "Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "Siemens SINEC NMS", "Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP" ], "cwes": [ "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.", "status": "Analyzed", "score_type": "Primary", "scores": { "cvss_v40": null, "cvss_v31": 7.5, "cvss_v30": null }, "references": [ { "url": "http://www.openwall.com/lists/oss-security/2023/10/10/6", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "http://www.openwall.com/lists/oss-security/2023/10/10/7", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "http://www.openwall.com/lists/oss-security/2023/10/13/4", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "http://www.openwall.com/lists/oss-security/2023/10/13/9", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "http://www.openwall.com/lists/oss-security/2023/10/18/4", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "http://www.openwall.com/lists/oss-security/2023/10/18/8", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "http://www.openwall.com/lists/oss-security/2023/10/19/6", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "http://www.openwall.com/lists/oss-security/2023/10/20/8", "tags": [ "Mailing List", "Third Party Advisory" ] }, { "url": "https://access.redhat.com/security/cve/cve-2023-44487", "tags": [ "Vendor Advisory" ] }, { "url": "https://arstechnica.com/security/2023/10/how-ddosers-used-the-http-2-protocol-to-deliver-attacks-of-unprecedented-size/", "tags": [ "Press/Media Coverage", "Third Party Advisory" ] }, { "url": "https://aws.amazon.com/security/security-bulletins/AWS-2023-011/", "tags": [ "Third Party Advisory" ] }, { "url": "https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/", "tags": [ "Technical Description", "Vendor Advisory" ] }, { "url": "https://blog.cloudflare.com/zero-day-rapid-reset-http2-record-breaking-ddos-attack/", "tags": [ "Third Party Advisory", "Vendor Advisory" ] }, { "url": "https://blog.litespeedtech.com/2023/10/11/rapid-reset-http-2-vulnerablilty/", "tags": [ "Vendor Advisory" ] }, { "url": "https://blog.qualys.com/vulnerabilities-threat-research/2023/10/10/cve-2023-44487-http-2-rapid-reset-attack", "tags": [ "Press/Media Coverage", "Third Party Advisory" ] }, { "url": "https://blog.vespa.ai/cve-2023-44487/", "tags": [ "Vendor Advisory" ] }, { "url": "https://bugzilla.proxmox.com/show_bug.cgi?id=4988", "tags": [ "Issue Tracking", "Third Party Advisory" ] }, { "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2242803", "tags": [ "Issue Tracking", "Vendor Advisory" ] }, { "url": "https://bugzilla.suse.com/show_bug.cgi?id=1216123", "tags": [ "Issue Tracking", "Vendor Advisory" ] }, { "url": "https://cgit.freebsd.org/ports/commit/?id=c64c329c2c1752f46b73e3e6ce9f4329be6629f9", "tags": [ "Mailing List", "Patch", "Vendor Advisory" ] }, { "url": "https://cloud.google.com/blog/products/identity-security/google-cloud-mitigated-largest-ddos-attack-peaking-above-398-million-rps/", "tags": [ "Technical Description", "Vendor Advisory" ] }, { "url": "https://cloud.google.com/blog/products/identity-security/how-it-works-the-novel-http2-rapid-reset-ddos-attack", "tags": [ "Technical Description", "Vendor Advisory" ] }, { "url": "https://community.traefik.io/t/is-traefik-vulnerable-to-cve-2023-44487/20125", "tags": [ "Vendor Advisory" ] }, { "url": "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", "tags": [ "Third Party Advisory" ] }, { "url": "https://edg.io/lp/blog/resets-leaks-ddos-and-the-tale-of-a-hidden-cve", "tags": [ "Broken Link" ] } ], "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2023-44487", "covered_in": [], "attribution": [ { "source": "NVD", "url": "https://nvd.nist.gov", "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD." }, { "source": "CISA KEV", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "notice": "Known exploited vulnerabilities from the CISA KEV catalog." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss", "notice": "Exploit prediction scores from FIRST EPSS." } ] }