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CVE-2023-44487
The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly,…
High7.5Known exploitedPublic exploitEPSS 100.0%
- Published
- Updated
- Reserved
- Assigned by
- mitre
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.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as HTTP/2 Rapid Reset Attack Vulnerability.
- Added
- 10 Oct 2023
- Fix due (US federal)
- 31 Oct 2023
- Used by ransomware
- Not known
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: it is being exploited.
Timeline
ID reserved
By mitre
- 11 days later
· 11 days later
Published
Added to CISA KEV
Known exploited in the wild
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Analyzed | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 100.0% · top 0.1% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: yes · Technical impact: partial
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
Affected products
n/a
- affected n/a
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogolang.org/x/netGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavencom.typesafe.akka:akka-http-coreGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavencom.typesafe.akka:akka-http-core_2.11GHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavencom.typesafe.akka:akka-http-core_2.12GHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavencom.typesafe.akka:akka-http-core_2.13GHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavenorg.apache.tomcat.embed:tomcat-embed-coreGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavenorg.apache.tomcat:tomcat-coyoteGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavenorg.eclipse.jetty.http2:http2-commonGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavenorg.eclipse.jetty.http2:http2-serverGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavenorg.eclipse.jetty.http2:jetty-http2-commonGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- Mavenorg.eclipse.jetty.http2:jetty-http2-serverGHSA-qppj-fm5r-hxr3 (opens in a new tab)
- SwiftURLgithub.com/apple/swift-nio-http2GHSA-qppj-fm5r-hxr3 (opens in a new tab)
References (173)
- https://github.com/dotnet/core/blob/e4613450ea0da7fd2fc6b61dfb2c1c1dec1ce9ec/release-notes/6.0/6.0.23/6.0.23.md?plain=1#L73 (opens in a new tab)x_transferred
- https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/ (opens in a new tab)x_transferred
- https://aws.amazon.com/security/security-bulletins/AWS-2023-011/ (opens in a new tab)x_transferred
- https://cloud.google.com/blog/products/identity-security/how-it-works-the-novel-http2-rapid-reset-ddos-attack (opens in a new tab)x_transferred
- https://www.nginx.com/blog/http-2-rapid-reset-attack-impacting-f5-nginx-products/ (opens in a new tab)x_transferred
- https://cloud.google.com/blog/products/identity-security/google-cloud-mitigated-largest-ddos-attack-peaking-above-398-million-rps/ (opens in a new tab)x_transferred
- https://news.ycombinator.com/item?id=37831062 (opens in a new tab)x_transferred
- https://blog.cloudflare.com/zero-day-rapid-reset-http2-record-breaking-ddos-attack/ (opens in a new tab)x_transferred
- https://www.phoronix.com/news/HTTP2-Rapid-Reset-Attack (opens in a new tab)x_transferred
- https://github.com/envoyproxy/envoy/pull/30055 (opens in a new tab)x_transferred
- https://github.com/haproxy/haproxy/issues/2312 (opens in a new tab)x_transferred
- https://github.com/eclipse/jetty.project/issues/10679 (opens in a new tab)x_transferred
- https://forums.swift.org/t/swift-nio-http2-security-update-cve-2023-44487-http-2-dos/67764 (opens in a new tab)x_transferred
- https://github.com/nghttp2/nghttp2/pull/1961 (opens in a new tab)x_transferred
- https://github.com/netty/netty/commit/58f75f665aa81a8cbcf6ffa74820042a285c5e61 (opens in a new tab)x_transferred
- https://github.com/alibaba/tengine/issues/1872 (opens in a new tab)x_transferred
- https://github.com/apache/tomcat/tree/main/java/org/apache/coyote/http2 (opens in a new tab)x_transferred
- https://news.ycombinator.com/item?id=37830987 (opens in a new tab)x_transferred
- https://news.ycombinator.com/item?id=37830998 (opens in a new tab)x_transferred
- https://github.com/caddyserver/caddy/issues/5877 (opens in a new tab)x_transferred
- https://www.bleepingcomputer.com/news/security/new-http-2-rapid-reset-zero-day-attack-breaks-ddos-records/ (opens in a new tab)x_transferred
- https://github.com/bcdannyboy/CVE-2023-44487 (opens in a new tab)x_transferred
- https://github.com/grpc/grpc-go/pull/6703 (opens in a new tab)x_transferred
- https://github.com/icing/mod_h2/blob/0a864782af0a942aa2ad4ed960a6b32cd35bcf0a/mod_http2/README.md?plain=1#L239-L244 (opens in a new tab)x_transferred
- https://github.com/nghttp2/nghttp2/releases/tag/v1.57.0 (opens in a new tab)x_transferred
- https://mailman.nginx.org/pipermail/nginx-devel/2023-October/S36Q5HBXR7CAIMPLLPRSSSYR4PCMWILK.html (opens in a new tab)x_transferred
- https://my.f5.com/manage/s/article/K000137106 (opens in a new tab)x_transferred
- https://msrc.microsoft.com/blog/2023/10/microsoft-response-to-distributed-denial-of-service-ddos-attacks-against-http/2/ (opens in a new tab)x_transferred
- https://bugzilla.proxmox.com/show_bug.cgi?id=4988 (opens in a new tab)x_transferred
- https://cgit.freebsd.org/ports/commit/?id=c64c329c2c1752f46b73e3e6ce9f4329be6629f9 (opens in a new tab)x_transferred
- [oss-security] 20231010 Re: CVE-2023-44487: HTTP/2 Rapid Reset attack against many implementations (opens in a new tab)mailing-list
- [oss-security] 20231010 CVE-2023-44487: HTTP/2 Rapid Reset attack against many implementations (opens in a new tab)mailing-list
- https://seanmonstar.com/post/730794151136935936/hyper-http2-rapid-reset-unaffected (opens in a new tab)x_transferred
- https://github.com/microsoft/CBL-Mariner/pull/6381 (opens in a new tab)x_transferred
- https://groups.google.com/g/golang-announce/c/iNNxDTCjZvo (opens in a new tab)x_transferred
- https://github.com/facebook/proxygen/pull/466 (opens in a new tab)x_transferred
- https://gist.github.com/adulau/7c2bfb8e9cdbe4b35a5e131c66a0c088 (opens in a new tab)x_transferred
- https://github.com/micrictor/http2-rst-stream (opens in a new tab)x_transferred
- https://edg.io/lp/blog/resets-leaks-ddos-and-the-tale-of-a-hidden-cve (opens in a new tab)x_transferred
- https://openssf.org/blog/2023/10/10/http-2-rapid-reset-vulnerability-highlights-need-for-rapid-response/ (opens in a new tab)x_transferred
- https://github.com/h2o/h2o/security/advisories/GHSA-2m7v-gc89-fjqf (opens in a new tab)x_transferred
- https://github.com/h2o/h2o/pull/3291 (opens in a new tab)x_transferred
- https://github.com/nodejs/node/pull/50121 (opens in a new tab)x_transferred
- https://github.com/dotnet/announcements/issues/277 (opens in a new tab)x_transferred
- https://github.com/golang/go/issues/63417 (opens in a new tab)x_transferred
- https://github.com/advisories/GHSA-vx74-f528-fxqg (opens in a new tab)x_transferred
- https://github.com/apache/trafficserver/pull/10564 (opens in a new tab)x_transferred
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-44487 (opens in a new tab)x_transferred
- https://tomcat.apache.org/security-10.html#Fixed_in_Apache_Tomcat_10.1.14 (opens in a new tab)x_transferred
- https://lists.apache.org/thread/5py8h42mxfsn8l1wy6o41xwhsjlsd87q (opens in a new tab)x_transferred
- https://www.openwall.com/lists/oss-security/2023/10/10/6 (opens in a new tab)x_transferred
- https://www.haproxy.com/blog/haproxy-is-not-affected-by-the-http-2-rapid-reset-attack-cve-2023-44487 (opens in a new tab)x_transferred
- https://github.com/opensearch-project/data-prepper/issues/3474 (opens in a new tab)x_transferred
- https://github.com/kubernetes/kubernetes/pull/121120 (opens in a new tab)x_transferred
- https://github.com/oqtane/oqtane.framework/discussions/3367 (opens in a new tab)x_transferred
- https://github.com/advisories/GHSA-xpw8-rcwv-8f8p (opens in a new tab)x_transferred
- https://netty.io/news/2023/10/10/4-1-100-Final.html (opens in a new tab)x_transferred
- https://www.cisa.gov/news-events/alerts/2023/10/10/http2-rapid-reset-vulnerability-cve-2023-44487 (opens in a new tab)x_transferred
- https://www.theregister.com/2023/10/10/http2_rapid_reset_zeroday/ (opens in a new tab)x_transferred
- https://blog.qualys.com/vulnerabilities-threat-research/2023/10/10/cve-2023-44487-http-2-rapid-reset-attack (opens in a new tab)x_transferred
- https://news.ycombinator.com/item?id=37837043 (opens in a new tab)x_transferred
- https://github.com/kazu-yamamoto/http2/issues/93 (opens in a new tab)x_transferred
- https://martinthomson.github.io/h2-stream-limits/draft-thomson-httpbis-h2-stream-limits.html (opens in a new tab)x_transferred
- https://github.com/kazu-yamamoto/http2/commit/f61d41a502bd0f60eb24e1ce14edc7b6df6722a1 (opens in a new tab)x_transferred
- https://github.com/apache/httpd/blob/afcdbeebbff4b0c50ea26cdd16e178c0d1f24152/modules/http2/h2_mplx.c#L1101-L1113 (opens in a new tab)x_transferred
- DSA-5522 (opens in a new tab)vendor-advisoryx_transferred
- DSA-5521 (opens in a new tab)vendor-advisoryx_transferred
- https://access.redhat.com/security/cve/cve-2023-44487 (opens in a new tab)x_transferred
- https://github.com/ninenines/cowboy/issues/1615 (opens in a new tab)x_transferred
- https://github.com/varnishcache/varnish-cache/issues/3996 (opens in a new tab)x_transferred
- https://github.com/tempesta-tech/tempesta/issues/1986 (opens in a new tab)x_transferred
- https://blog.vespa.ai/cve-2023-44487/ (opens in a new tab)x_transferred
- https://github.com/etcd-io/etcd/issues/16740 (opens in a new tab)x_transferred
- https://www.darkreading.com/cloud/internet-wide-zero-day-bug-fuels-largest-ever-ddos-event (opens in a new tab)x_transferred
- https://istio.io/latest/news/security/istio-security-2023-004/ (opens in a new tab)x_transferred
- https://github.com/junkurihara/rust-rpxy/issues/97 (opens in a new tab)x_transferred
- https://bugzilla.suse.com/show_bug.cgi?id=1216123 (opens in a new tab)x_transferred
- https://bugzilla.redhat.com/show_bug.cgi?id=2242803 (opens in a new tab)x_transferred
- https://ubuntu.com/security/CVE-2023-44487 (opens in a new tab)x_transferred
- https://community.traefik.io/t/is-traefik-vulnerable-to-cve-2023-44487/20125 (opens in a new tab)x_transferred
- https://github.com/advisories/GHSA-qppj-fm5r-hxr3 (opens in a new tab)x_transferred
- https://github.com/apache/httpd-site/pull/10 (opens in a new tab)x_transferred
- https://github.com/projectcontour/contour/pull/5826 (opens in a new tab)x_transferred
- https://github.com/linkerd/website/pull/1695/commits/4b9c6836471bc8270ab48aae6fd2181bc73fd632 (opens in a new tab)x_transferred
- https://github.com/line/armeria/pull/5232 (opens in a new tab)x_transferred
- https://blog.litespeedtech.com/2023/10/11/rapid-reset-http-2-vulnerablilty/ (opens in a new tab)x_transferred
- https://security.paloaltonetworks.com/CVE-2023-44487 (opens in a new tab)x_transferred
- https://github.com/akka/akka-http/issues/4323 (opens in a new tab)x_transferred
- https://github.com/openresty/openresty/issues/930 (opens in a new tab)x_transferred
- https://github.com/apache/apisix/issues/10320 (opens in a new tab)x_transferred
- https://github.com/Azure/AKS/issues/3947 (opens in a new tab)x_transferred
- https://github.com/Kong/kong/discussions/11741 (opens in a new tab)x_transferred
- https://github.com/arkrwn/PoC/tree/main/CVE-2023-44487 (opens in a new tab)x_transferred
- https://www.netlify.com/blog/netlify-successfully-mitigates-cve-2023-44487/ (opens in a new tab)x_transferred
- https://github.com/caddyserver/caddy/releases/tag/v2.7.5 (opens in a new tab)x_transferred
- [debian-lts-announce] 20231013 [SECURITY] [DLA 3617-1] tomcat9 security update (opens in a new tab)mailing-listx_transferred
- [oss-security] 20231013 Re: CVE-2023-44487: HTTP/2 Rapid Reset attack against many implementations (opens in a new tab)mailing-listx_transferred
- [oss-security] 20231013 Re: CVE-2023-44487: HTTP/2 Rapid Reset attack against many implementations (opens in a new tab)mailing-listx_transferred
- https://arstechnica.com/security/2023/10/how-ddosers-used-the-http-2-protocol-to-deliver-attacks-of-unprecedented-size/ (opens in a new tab)x_transferred
- https://lists.w3.org/Archives/Public/ietf-http-wg/2023OctDec/0025.html (opens in a new tab)x_transferred
- FEDORA-2023-ed2642fd58 (opens in a new tab)vendor-advisory
- https://linkerd.io/2023/10/12/linkerd-cve-2023-44487/ (opens in a new tab)x_transferred
- [debian-lts-announce] 20231016 [SECURITY] [DLA 3621-1] nghttp2 security update (opens in a new tab)mailing-listx_transferred
- https://security.netapp.com/advisory/ntap-20231016-0001/ (opens in a new tab)x_transferred
- [debian-lts-announce] 20231016 [SECURITY] [DLA 3617-2] tomcat9 regression update (opens in a new tab)mailing-listx_transferred
- [oss-security] 20231018 Vulnerability in Jenkins (opens in a new tab)mailing-listx_transferred
- [oss-security] 20231018 Re: CVE-2023-44487: HTTP/2 Rapid Reset attack against many implementations (opens in a new tab)mailing-listx_transferred
- [oss-security] 20231019 CVE-2023-45802: Apache HTTP Server: HTTP/2 stream memory not reclaimed right away on RST (opens in a new tab)mailing-listx_transferred
- FEDORA-2023-54fadada12 (opens in a new tab)vendor-advisory
- FEDORA-2023-5ff7bf1dd8 (opens in a new tab)vendor-advisory
- [oss-security] 20231020 Re: CVE-2023-44487: HTTP/2 Rapid Reset attack against many implementations (opens in a new tab)mailing-listx_transferred
- FEDORA-2023-17efd3f2cd (opens in a new tab)vendor-advisory
- FEDORA-2023-d5030c983c (opens in a new tab)vendor-advisory
- FEDORA-2023-0259c3f26f (opens in a new tab)vendor-advisory
- FEDORA-2023-2a9214af5f (opens in a new tab)vendor-advisory
- FEDORA-2023-e9c04d81c1 (opens in a new tab)vendor-advisory
- FEDORA-2023-f66fc0f62a (opens in a new tab)vendor-advisory
- FEDORA-2023-4d2fd884ea (opens in a new tab)vendor-advisory
- FEDORA-2023-b2c50535cb (opens in a new tab)vendor-advisory
- FEDORA-2023-fe53e13b5b (opens in a new tab)vendor-advisory
- FEDORA-2023-4bf641255e (opens in a new tab)vendor-advisory
- [debian-lts-announce] 20231030 [SECURITY] [DLA 3641-1] jetty9 security update (opens in a new tab)mailing-listx_transferred
- DSA-5540 (opens in a new tab)vendor-advisoryx_transferred
- [debian-lts-announce] 20231031 [SECURITY] [DLA 3638-1] h2o security update (opens in a new tab)mailing-listx_transferred
- 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 (opens in a new tab)x_transferred
- FEDORA-2023-1caffb88af (opens in a new tab)vendor-advisory
- FEDORA-2023-3f70b8d406 (opens in a new tab)vendor-advisory
- FEDORA-2023-7b52921cae (opens in a new tab)vendor-advisory
- FEDORA-2023-7934802344 (opens in a new tab)vendor-advisory
- FEDORA-2023-dbe64661af (opens in a new tab)vendor-advisory
- FEDORA-2023-822aab0a5a (opens in a new tab)vendor-advisory
- [debian-lts-announce] 20231105 [SECURITY] [DLA 3645-1] trafficserver security update (opens in a new tab)mailing-listx_transferred
- DSA-5549 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-c0c6a91330 (opens in a new tab)vendor-advisory
- FEDORA-2023-492b7be466 (opens in a new tab)vendor-advisory
- DSA-5558 (opens in a new tab)vendor-advisoryx_transferred
- [debian-lts-announce] 20231119 [SECURITY] [DLA 3656-1] netty security update (opens in a new tab)mailing-listx_transferred
- GLSA-202311-09 (opens in a new tab)vendor-advisoryx_transferred
- DSA-5570 (opens in a new tab)vendor-advisoryx_transferred
- https://security.netapp.com/advisory/ntap-20240426-0007/ (opens in a new tab)x_transferred
- https://security.netapp.com/advisory/ntap-20240621-0006/ (opens in a new tab)x_transferred
- https://security.netapp.com/advisory/ntap-20240621-0007/ (opens in a new tab)x_transferred
- https://github.com/grpc/grpc/releases/tag/v1.59.2 (opens in a new tab)
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-http2-reset-d8Kf32vZ (opens in a new tab)
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-44487 (opens in a new tab)government-resource
- FEDORA-2023-ed2642fd58 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-54fadada12 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-5ff7bf1dd8 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-17efd3f2cd (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-d5030c983c (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-0259c3f26f (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-2a9214af5f (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-e9c04d81c1 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-f66fc0f62a (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-4d2fd884ea (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-b2c50535cb (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-fe53e13b5b (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-4bf641255e (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-1caffb88af (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-3f70b8d406 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-7b52921cae (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-7934802344 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-dbe64661af (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-822aab0a5a (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-c0c6a91330 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2023-492b7be466 (opens in a new tab)vendor-advisoryx_transferred
- https://www.vicarius.io/vsociety/posts/rapid-reset-cve-2023-44487-dos-in-http2-understanding-the-root-cause (opens in a new tab)
- http://www.openwall.com/lists/oss-security/2025/08/13/6 (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-832273.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-341067.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-784301.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-915275.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-qppj-fm5r-hxr3 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2023-44487)Record last updated .