Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write (many of) the bytes on the wire. The attacker then sends a stream of requests for a large response object. Depending on how the servers queue the responses, this can consume excess memory, CPU, or both.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Swiftnio | Apple | 1.0.0 (including) | 1.4.0 (including) |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-httpd-0:2.4.29-41.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-nghttp2-0:1.39.2-1.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-apr-0:1.6.3-63.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-apr-util-0:1.6.1-48.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-brotli-0:1.0.6-7.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-curl-0:7.64.1-14.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-httpd-0:2.4.37-33.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-jansson-0:2.11-20.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-mod_cluster-native-0:1.3.12-9.Final_redhat_2.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-mod_jk-0:1.2.46-22.redhat_1.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-mod_security-0:2.9.2-16.GA.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-nghttp2-0:1.39.2-4.jbcs.el6 | * |
| JBoss Core Services on RHEL 6 | RedHat | jbcs-httpd24-openssl-1:1.1.1-25.jbcs.el6 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-httpd-0:2.4.29-41.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-nghttp2-0:1.39.2-1.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-apr-0:1.6.3-63.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-apr-util-0:1.6.1-48.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-brotli-0:1.0.6-7.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-curl-0:7.64.1-14.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-httpd-0:2.4.37-33.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-jansson-0:2.11-20.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-mod_cluster-native-0:1.3.12-9.Final_redhat_2.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-mod_jk-0:1.2.46-22.redhat_1.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-mod_security-0:2.9.2-16.GA.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-nghttp2-0:1.39.2-4.jbcs.el7 | * |
| JBoss Core Services on RHEL 7 | RedHat | jbcs-httpd24-openssl-1:1.1.1-25.jbcs.el7 | * |
| Red Hat AMQ | RedHat | jetty | * |
| Red Hat AMQ 7.4.3 | RedHat | jetty | * |
| Red Hat Enterprise Linux 8 | RedHat | httpd:2.4-8000020190829150747.f8e95b4e | * |
| Red Hat Enterprise Linux 8 | RedHat | nodejs:10-8000020190911085529.f8e95b4e | * |
| Red Hat Fuse 7.6.0 | RedHat | undertow | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | RedHat | httpd24-httpd-0:2.4.34-8.el6.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 6 | RedHat | httpd24-nghttp2-0:1.7.1-7.el6.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | RedHat | rh-nodejs10-0:3.2-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | RedHat | rh-nodejs10-nodejs-0:10.16.3-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | RedHat | httpd24-httpd-0:2.4.34-8.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | RedHat | httpd24-nghttp2-0:1.7.1-7.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | RedHat | rh-nodejs8-0:3.0-5.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7 | RedHat | rh-nodejs8-nodejs-0:8.16.1-2.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | RedHat | rh-nodejs10-0:3.2-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | RedHat | rh-nodejs10-nodejs-0:10.16.3-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | RedHat | httpd24-httpd-0:2.4.34-8.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | RedHat | httpd24-nghttp2-0:1.7.1-7.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | RedHat | rh-nodejs8-0:3.0-5.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS | RedHat | rh-nodejs8-nodejs-0:8.16.1-2.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | RedHat | rh-nodejs10-0:3.2-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | RedHat | rh-nodejs10-nodejs-0:10.16.3-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | RedHat | httpd24-httpd-0:2.4.34-8.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | RedHat | httpd24-nghttp2-0:1.7.1-7.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | RedHat | rh-nodejs8-0:3.0-5.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS | RedHat | rh-nodejs8-nodejs-0:8.16.1-2.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS | RedHat | rh-nodejs10-0:3.2-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS | RedHat | rh-nodejs10-nodejs-0:10.16.3-3.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS | RedHat | httpd24-httpd-0:2.4.34-8.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS | RedHat | httpd24-nghttp2-0:1.7.1-7.el7.1 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS | RedHat | rh-nodejs8-0:3.0-5.el7 | * |
| Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS | RedHat | rh-nodejs8-nodejs-0:8.16.1-2.el7 | * |
| Text-Only JBCS | RedHat | mod_http2 | * |
| Text-Only JBCS | RedHat | mod_http2 | * |
| Apache2 | Ubuntu | bionic | * |
| Apache2 | Ubuntu | cosmic | * |
| Apache2 | Ubuntu | disco | * |
| Apache2 | Ubuntu | esm-infra/bionic | * |
| Apache2 | Ubuntu | trusty | * |
| Apache2 | Ubuntu | upstream | * |
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.