{"schema":"threatline.record/2","record":{"id":"CVE-2023-44487","aliases":["GHSA-2m7v-gc89-fjqf","GHSA-vx74-f528-fxqg","GHSA-xpw8-rcwv-8f8p"],"summary":"HTTP/2 Rapid Reset Attack Vulnerability","details":"HTTP/2 contains a rapid reset vulnerability that allows for a distributed denial-of-service attack (DDoS).","categories":["Unclassified"],"product":"HTTP/2","vendor":"IETF","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2023-44487","source_modified_at":"2026-10-14T23:51:51.782Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"n/a","vendor":"n/a","versions":[{"version":"n/a","status":"affected"}],"defaultStatus":null}],"fixed_versions":[],"cvss":7.5,"severity":"High","kev":{"listed":true,"date_added":"2023-10-10","due_date":"2023-10-31","required_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_campaign_use":"Unknown"},"epss":{"probability":0.99999,"percentile":0.99999,"score_date":"2026-10-23"},"published_at":"2023-10-10T00:00:00.000Z","modified_at":"2026-10-14T23:51:51.782Z","provenance":[{"source":"CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T17:00:09.9001Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2023-44487","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-14T23:51:51.782Z"},{"source":"Exploit-DB","url":"https://www.exploit-db.com/exploits/52426","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2025-09-16"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2023-44487","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CISA KEV","CVE List","Exploit-DB","EPSS"],"references":[{"source":"CVE List","url":"https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/","tags":["x_transferred"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-44487","source":"CISA KEV"},{"source":"CVE List","url":"https://github.com/dotnet/core/blob/e4613450ea0da7fd2fc6b61dfb2c1c1dec1ce9ec/release-notes/6.0/6.0.23/6.0.23.md?plain=1#L73","tags":["x_transferred"]},{"source":"CVE List","url":"https://aws.amazon.com/security/security-bulletins/AWS-2023-011/","tags":["x_transferred"]},{"source":"CVE List","url":"https://cloud.google.com/blog/products/identity-security/how-it-works-the-novel-http2-rapid-reset-ddos-attack","tags":["x_transferred"]},{"source":"CVE List","url":"https://www.nginx.com/blog/http-2-rapid-reset-attack-impacting-f5-nginx-products/","tags":["x_transferred"]},{"source":"CVE List","url":"https://cloud.google.com/blog/products/identity-security/google-cloud-mitigated-largest-ddos-attack-peaking-above-398-million-rps/","tags":["x_transferred"]},{"source":"CVE List","url":"https://news.ycombinator.com/item?id=37831062","tags":["x_transferred"]},{"source":"CVE List","url":"https://blog.cloudflare.com/zero-day-rapid-reset-http2-record-breaking-ddos-attack/","tags":["x_transferred"]},{"source":"CVE List","url":"https://www.phoronix.com/news/HTTP2-Rapid-Reset-Attack","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/envoyproxy/envoy/pull/30055","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/haproxy/haproxy/issues/2312","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/eclipse/jetty.project/issues/10679","tags":["x_transferred"]},{"source":"CVE List","url":"https://forums.swift.org/t/swift-nio-http2-security-update-cve-2023-44487-http-2-dos/67764","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/nghttp2/nghttp2/pull/1961","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/netty/netty/commit/58f75f665aa81a8cbcf6ffa74820042a285c5e61","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/alibaba/tengine/issues/1872","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/apache/tomcat/tree/main/java/org/apache/coyote/http2","tags":["x_transferred"]},{"source":"CVE List","url":"https://news.ycombinator.com/item?id=37830987","tags":["x_transferred"]},{"source":"CVE List","url":"https://news.ycombinator.com/item?id=37830998","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/caddyserver/caddy/issues/5877","tags":["x_transferred"]},{"source":"CVE List","url":"https://www.bleepingcomputer.com/news/security/new-http-2-rapid-reset-zero-day-attack-breaks-ddos-records/","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/bcdannyboy/CVE-2023-44487","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/grpc/grpc-go/pull/6703","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/icing/mod_h2/blob/0a864782af0a942aa2ad4ed960a6b32cd35bcf0a/mod_http2/README.md?plain=1#L239-L244","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/nghttp2/nghttp2/releases/tag/v1.57.0","tags":["x_transferred"]},{"source":"CVE List","url":"https://mailman.nginx.org/pipermail/nginx-devel/2023-October/S36Q5HBXR7CAIMPLLPRSSSYR4PCMWILK.html","tags":["x_transferred"]},{"source":"CVE List","url":"https://my.f5.com/manage/s/article/K000137106","tags":["x_transferred"]},{"source":"CVE List","url":"https://msrc.microsoft.com/blog/2023/10/microsoft-response-to-distributed-denial-of-service-ddos-attacks-against-http/2/","tags":["x_transferred"]},{"source":"CVE List","url":"https://bugzilla.proxmox.com/show_bug.cgi?id=4988","tags":["x_transferred"]},{"source":"CVE List","url":"https://cgit.freebsd.org/ports/commit/?id=c64c329c2c1752f46b73e3e6ce9f4329be6629f9","tags":["x_transferred"]},{"source":"CVE List","url":"https://seanmonstar.com/post/730794151136935936/hyper-http2-rapid-reset-unaffected","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/microsoft/CBL-Mariner/pull/6381","tags":["x_transferred"]},{"source":"CVE List","url":"https://groups.google.com/g/golang-announce/c/iNNxDTCjZvo","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/facebook/proxygen/pull/466","tags":["x_transferred"]},{"source":"CVE List","url":"https://gist.github.com/adulau/7c2bfb8e9cdbe4b35a5e131c66a0c088","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/micrictor/http2-rst-stream","tags":["x_transferred"]},{"source":"CVE List","url":"https://edg.io/lp/blog/resets-leaks-ddos-and-the-tale-of-a-hidden-cve","tags":["x_transferred"]},{"source":"CVE List","url":"https://openssf.org/blog/2023/10/10/http-2-rapid-reset-vulnerability-highlights-need-for-rapid-response/","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/h2o/h2o/security/advisories/GHSA-2m7v-gc89-fjqf","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/h2o/h2o/pull/3291","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/nodejs/node/pull/50121"},{"source":"CVE List","url":"https://github.com/dotnet/announcements/issues/277"},{"source":"CVE List","url":"https://github.com/golang/go/issues/63417"},{"source":"CVE List","url":"https://github.com/advisories/GHSA-vx74-f528-fxqg"},{"source":"CVE List","url":"https://github.com/apache/trafficserver/pull/10564"},{"source":"CVE List","url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-44487"},{"source":"CVE List","url":"https://tomcat.apache.org/security-10.html#Fixed_in_Apache_Tomcat_10.1.14"},{"source":"CVE List","url":"https://lists.apache.org/thread/5py8h42mxfsn8l1wy6o41xwhsjlsd87q"},{"source":"CVE List","url":"https://www.openwall.com/lists/oss-security/2023/10/10/6"},{"source":"CVE List","url":"https://www.haproxy.com/blog/haproxy-is-not-affected-by-the-http-2-rapid-reset-attack-cve-2023-44487"},{"source":"CVE List","url":"https://github.com/opensearch-project/data-prepper/issues/3474"},{"source":"CVE List","url":"https://github.com/kubernetes/kubernetes/pull/121120"},{"source":"CVE List","url":"https://github.com/oqtane/oqtane.framework/discussions/3367"},{"source":"CVE List","url":"https://github.com/advisories/GHSA-xpw8-rcwv-8f8p"},{"source":"CVE List","url":"https://netty.io/news/2023/10/10/4-1-100-Final.html"},{"source":"CVE List","url":"https://www.cisa.gov/news-events/alerts/2023/10/10/http2-rapid-reset-vulnerability-cve-2023-44487"},{"source":"CVE List","url":"https://www.theregister.com/2023/10/10/http2_rapid_reset_zeroday/"},{"source":"CVE List","url":"https://blog.qualys.com/vulnerabilities-threat-research/2023/10/10/cve-2023-44487-http-2-rapid-reset-attack"},{"source":"CVE List","url":"https://news.ycombinator.com/item?id=37837043"},{"source":"CVE List","url":"https://github.com/kazu-yamamoto/http2/issues/93"},{"source":"CVE List","url":"https://martinthomson.github.io/h2-stream-limits/draft-thomson-httpbis-h2-stream-limits.html"},{"source":"CVE List","url":"https://github.com/kazu-yamamoto/http2/commit/f61d41a502bd0f60eb24e1ce14edc7b6df6722a1"},{"source":"CVE List","url":"https://github.com/apache/httpd/blob/afcdbeebbff4b0c50ea26cdd16e178c0d1f24152/modules/http2/h2_mplx.c#L1101-L1113"},{"source":"CVE List","url":"https://www.debian.org/security/2023/dsa-5522","tags":["vendor-advisory"]},{"source":"CVE List","url":"https://www.debian.org/security/2023/dsa-5521","tags":["vendor-advisory"]},{"source":"CVE List","url":"https://access.redhat.com/security/cve/cve-2023-44487"},{"source":"CVE List","url":"https://github.com/ninenines/cowboy/issues/1615"},{"source":"CVE List","url":"https://github.com/varnishcache/varnish-cache/issues/3996"},{"source":"CVE List","url":"https://github.com/tempesta-tech/tempesta/issues/1986"},{"source":"CVE List","url":"https://blog.vespa.ai/cve-2023-44487/"},{"source":"CVE List","url":"https://github.com/etcd-io/etcd/issues/16740"},{"source":"CVE List","url":"https://www.darkreading.com/cloud/internet-wide-zero-day-bug-fuels-largest-ever-ddos-event"},{"source":"CVE List","url":"https://istio.io/latest/news/security/istio-security-2023-004/"},{"source":"CVE List","url":"https://github.com/junkurihara/rust-rpxy/issues/97"},{"source":"CVE List","url":"https://bugzilla.suse.com/show_bug.cgi?id=1216123"},{"source":"CVE List","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2242803"},{"source":"CVE List","url":"https://ubuntu.com/security/CVE-2023-44487"},{"source":"CVE List","url":"https://community.traefik.io/t/is-traefik-vulnerable-to-cve-2023-44487/20125"},{"source":"CVE List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-44487","tags":["government-resource"]},{"source":"CVE List","url":"https://cert-portal.siemens.com/productcert/html/ssa-832273.html"},{"source":"CVE List","url":"https://cert-portal.siemens.com/productcert/html/ssa-341067.html"},{"source":"CVE List","url":"https://cert-portal.siemens.com/productcert/html/ssa-784301.html"},{"source":"CVE List","url":"https://cert-portal.siemens.com/productcert/html/ssa-915275.html"},{"source":"CVE List","url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CISA ADP","ssvc":{"exploitation":"active","automatable":"yes","technical_impact":"partial","assessed_at":"2024-07-23T20:34:21.334116Z"},"exploits":[{"source":"Exploit-DB","kind":"Remote exploit","name":"HTTP/2 2.0 - Denial Of Service (DOS)","url":"https://www.exploit-db.com/exploits/52426","date":"2025-09-16","added":"2025-09-16","verified":false}],"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-14T23:51:51.782Z","content_hash":"9c583f35abb739036c6a3ccddbc91ca521aa70cab51ce0568211d92db4c7f569"}}
