CVE-2019-9513: Some HTTP/2 implementations are vulnerable to resource loops, potentially leading to a denial of service

Published Aug 1, 2019
·
Updated

A flaw was found in HTTP/2. An attacker, using PRIORITY frames to flood the system, could cause excessive CPU usage and starvation of other clients. The largest threat from this vulnerability is to system availability.

Other sources

HTTP/2 flood using PRIORITY frames that results in excessive CPU usage and starvation of other clients.

— Red Hat

Some HTTP/2 implementations are vulnerable to resource loops, potentially leading to a denial of service. The attacker creates multiple request streams and continually shuffles the priority of the streams in a way that causes substantial churn to the priority tree. This can consume excess CPU.

Affected Software

95 affected componentsFixes available
redhat/jbcs-httpd24-httpd<0:2.4.29-41.jbcs.el6
0:2.4.29-41.jbcs.el6
redhat/jbcs-httpd24-nghttp2<0:1.39.2-1.jbcs.el6
0:1.39.2-1.jbcs.el6
redhat/jbcs-httpd24-apr<0:1.6.3-63.jbcs.el6
0:1.6.3-63.jbcs.el6
redhat/jbcs-httpd24-apr-util<0:1.6.1-48.jbcs.el6
0:1.6.1-48.jbcs.el6
redhat/jbcs-httpd24-brotli<0:1.0.6-7.jbcs.el6
0:1.0.6-7.jbcs.el6
redhat/jbcs-httpd24-curl<0:7.64.1-14.jbcs.el6
0:7.64.1-14.jbcs.el6
redhat/jbcs-httpd24-httpd<0:2.4.37-33.jbcs.el6
0:2.4.37-33.jbcs.el6
redhat/jbcs-httpd24-jansson<0:2.11-20.jbcs.el6
0:2.11-20.jbcs.el6
redhat/jbcs-httpd24-nghttp2<0:1.39.2-4.jbcs.el6
0:1.39.2-4.jbcs.el6
redhat/jbcs-httpd24-openssl<1:1.1.1-25.jbcs.el6
1:1.1.1-25.jbcs.el6
redhat/jbcs-httpd24-httpd<0:2.4.29-41.jbcs.el7
0:2.4.29-41.jbcs.el7
redhat/jbcs-httpd24-nghttp2<0:1.39.2-1.jbcs.el7
0:1.39.2-1.jbcs.el7
redhat/jbcs-httpd24-apr<0:1.6.3-63.jbcs.el7
0:1.6.3-63.jbcs.el7
redhat/jbcs-httpd24-apr-util<0:1.6.1-48.jbcs.el7
0:1.6.1-48.jbcs.el7
redhat/jbcs-httpd24-brotli<0:1.0.6-7.jbcs.el7
0:1.0.6-7.jbcs.el7
redhat/jbcs-httpd24-curl<0:7.64.1-14.jbcs.el7
0:7.64.1-14.jbcs.el7
redhat/jbcs-httpd24-httpd<0:2.4.37-33.jbcs.el7
0:2.4.37-33.jbcs.el7
redhat/jbcs-httpd24-jansson<0:2.11-20.jbcs.el7
0:2.11-20.jbcs.el7
redhat/jbcs-httpd24-nghttp2<0:1.39.2-4.jbcs.el7
0:1.39.2-4.jbcs.el7
redhat/jbcs-httpd24-openssl<1:1.1.1-25.jbcs.el7
1:1.1.1-25.jbcs.el7
redhat/kiali<0:v1.0.6.redhat1-1.el7
0:v1.0.6.redhat1-1.el7
redhat/servicemesh<0:1.0.1-8.el8
0:1.0.1-8.el8
redhat/servicemesh-cni<0:1.0.1-8.el8
0:1.0.1-8.el8
redhat/servicemesh-grafana<0:6.2.2-21.el8
0:6.2.2-21.el8
redhat/servicemesh-operator<0:1.0.1-8.el8
0:1.0.1-8.el8
redhat/servicemesh-prometheus<0:2.7.2-22.el8
0:2.7.2-22.el8
redhat/servicemesh-proxy<0:1.0.1-7.el8
0:1.0.1-7.el8
redhat/nghttp2<0:1.33.0-1.el8_0.1
0:1.33.0-1.el8_0.1
redhat/rh-nginx110-nginx<1:1.10.2-9.el6.1
1:1.10.2-9.el6.1
redhat/httpd24-httpd<0:2.4.34-8.el6.1
0:2.4.34-8.el6.1
redhat/httpd24-nghttp2<0:1.7.1-7.el6.1
0:1.7.1-7.el6.1
redhat/rh-nginx110-nginx<1:1.10.2-9.el7.1
1:1.10.2-9.el7.1
redhat/rh-nginx112-nginx<1:1.12.1-3.el7.1
1:1.12.1-3.el7.1
redhat/rh-nginx114-nginx<1:1.14.1-1.el7.1
1:1.14.1-1.el7.1
redhat/rh-nodejs10<0:3.2-3.el7
0:3.2-3.el7
redhat/rh-nodejs10-nodejs<0:10.16.3-3.el7
0:10.16.3-3.el7
redhat/httpd24-httpd<0:2.4.34-8.el7.1
0:2.4.34-8.el7.1
redhat/httpd24-nghttp2<0:1.7.1-7.el7.1
0:1.7.1-7.el7.1
redhat/rh-nodejs8<0:3.0-5.el7
0:3.0-5.el7
redhat/rh-nodejs8-nodejs<0:8.16.1-2.el7
0:8.16.1-2.el7
redhat/envoy<1.11.1
1.11.1
redhat/Nodejs<8.16.1
8.16.1
redhat/Nodejs<10.16.3
10.16.3
redhat/Nodejs<12.8.1
12.8.1
redhat/nginx<1.16.1
1.16.1
redhat/nginx<1.17.3
1.17.3
redhat/nghttp2<1.39.2
1.39.2
All of the following
Apple Swiftnio>=1.0.0<=1.4.0
Any of the following
Apple iOS and macOS>=10.12
Canonical Ubuntu Linux>=14.04
Apache Traffic Server>=6.0.0<=6.2.3
Apache Traffic Server>=7.0.0<=7.1.6
Apache Traffic Server>=8.0.0<=8.0.3
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=19.04
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Fedoraproject Fedora=30
Synology Skynas
Synology Diskstation Manager=6.2
All of the following
Synology Vs960hd Firmware
Synology Vs960hd
Fedoraproject Fedora=29
openSUSE Leap=15.0
openSUSE Leap=15.1
redhat JBoss Core Services=1.0
redhat JBoss Enterprise Application Platform=7.2.0
redhat JBoss Enterprise Application Platform=7.3.0
redhat Openshift Service Mesh=1.0
redhat Quay=3.0.0
redhat Software Collections=1.0
redhat Enterprise Linux=8.0
Oracle GraalVM=19.2.0
McAfee Web Gateway>=7.7.2.0<7.7.2.24
McAfee Web Gateway>=7.8.2.0<7.8.2.13
McAfee Web Gateway>=8.1.0<8.2.0
F5 Nginx>=1.9.5<1.16.1
F5 Nginx>=1.17.0<=1.17.2
Oracle Enterprise Communications Broker=3.1.0
Oracle Enterprise Communications Broker=3.2.0
Nodejs Node.js>=8.0.0<=8.8.1
Nodejs Node.js>=8.9.0<8.16.1
Nodejs Node.js>=10.0.0<=10.12.0
Nodejs Node.js>=10.13.0<10.16.3
Nodejs Node.js>=12.0.0<12.8.1
Apple Swiftnio>=1.0.0<=1.4.0
Apple iOS and macOS>=10.12
Canonical Ubuntu Linux>=14.04
Synology Diskstation Manager=6.2
Synology Vs960hd Firmware
Synology Vs960hd
debian/nghttp2
1.43.0-1+deb11u11.43.0-1+deb11u21.52.0-1+deb12u21.52.0-1+deb12u11.64.0-1.11.68.0-1
debian/nginx
1.18.0-6.1+deb11u31.18.0-6.1+deb11u51.22.1-9+deb12u31.22.1-9+deb12u41.26.3-3+deb13u11.26.3-3+deb13u21.28.2-2
debian/nodejs
12.22.12~dfsg-1~deb11u412.22.12~dfsg-1~deb11u718.20.4+dfsg-1~deb12u120.19.2+dfsg-122.22.0+dfsg+~cs22.19.6-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.29-41.jbcs.el6
  2. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-1.jbcs.el6
  3. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-63.jbcs.el6
  4. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-48.jbcs.el6
  5. Upgrade

    Upgrade redhat/jbcs-httpd24-brotli to a version that resolves this vulnerability.

    Fixed in 0:1.0.6-7.jbcs.el6
  6. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.64.1-14.jbcs.el6
  7. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-33.jbcs.el6
  8. Upgrade

    Upgrade redhat/jbcs-httpd24-jansson to a version that resolves this vulnerability.

    Fixed in 0:2.11-20.jbcs.el6
  9. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-4.jbcs.el6
  10. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.1.1-25.jbcs.el6
  11. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.29-41.jbcs.el7
  12. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-1.jbcs.el7
  13. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-63.jbcs.el7
  14. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-48.jbcs.el7
  15. Upgrade

    Upgrade redhat/jbcs-httpd24-brotli to a version that resolves this vulnerability.

    Fixed in 0:1.0.6-7.jbcs.el7
  16. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.64.1-14.jbcs.el7
  17. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-33.jbcs.el7
  18. Upgrade

    Upgrade redhat/jbcs-httpd24-jansson to a version that resolves this vulnerability.

    Fixed in 0:2.11-20.jbcs.el7
  19. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-4.jbcs.el7
  20. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.1.1-25.jbcs.el7
  21. Upgrade

    Upgrade redhat/kiali to a version that resolves this vulnerability.

    Fixed in 0:v1.0.6.redhat1-1.el7
  22. Upgrade

    Upgrade redhat/servicemesh to a version that resolves this vulnerability.

    Fixed in 0:1.0.1-8.el8
  23. Upgrade

    Upgrade redhat/servicemesh-cni to a version that resolves this vulnerability.

    Fixed in 0:1.0.1-8.el8
  24. Upgrade

    Upgrade redhat/servicemesh-grafana to a version that resolves this vulnerability.

    Fixed in 0:6.2.2-21.el8
  25. Upgrade

    Upgrade redhat/servicemesh-operator to a version that resolves this vulnerability.

    Fixed in 0:1.0.1-8.el8
  26. Upgrade

    Upgrade redhat/servicemesh-prometheus to a version that resolves this vulnerability.

    Fixed in 0:2.7.2-22.el8
  27. Upgrade

    Upgrade redhat/servicemesh-proxy to a version that resolves this vulnerability.

    Fixed in 0:1.0.1-7.el8
  28. Upgrade

    Upgrade redhat/nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.33.0-1.el8_0.1
  29. Upgrade

    Upgrade redhat/rh-nginx110-nginx to a version that resolves this vulnerability.

    Fixed in 1:1.10.2-9.el6.1
  30. Upgrade

    Upgrade redhat/httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.34-8.el6.1
  31. Upgrade

    Upgrade redhat/httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.7.1-7.el6.1
  32. Upgrade

    Upgrade redhat/rh-nginx110-nginx to a version that resolves this vulnerability.

    Fixed in 1:1.10.2-9.el7.1
  33. Upgrade

    Upgrade redhat/rh-nginx112-nginx to a version that resolves this vulnerability.

    Fixed in 1:1.12.1-3.el7.1
  34. Upgrade

    Upgrade redhat/rh-nginx114-nginx to a version that resolves this vulnerability.

    Fixed in 1:1.14.1-1.el7.1
  35. Upgrade

    Upgrade redhat/rh-nodejs10 to a version that resolves this vulnerability.

    Fixed in 0:3.2-3.el7
  36. Upgrade

    Upgrade redhat/rh-nodejs10-nodejs to a version that resolves this vulnerability.

    Fixed in 0:10.16.3-3.el7
  37. Upgrade

    Upgrade redhat/httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.34-8.el7.1
  38. Upgrade

    Upgrade redhat/httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.7.1-7.el7.1
  39. Upgrade

    Upgrade redhat/rh-nodejs8 to a version that resolves this vulnerability.

    Fixed in 0:3.0-5.el7
  40. Upgrade

    Upgrade redhat/rh-nodejs8-nodejs to a version that resolves this vulnerability.

    Fixed in 0:8.16.1-2.el7
  41. Upgrade

    Upgrade debian/nghttp2 to a version that resolves this vulnerability.

    Fixed in 1.43.0-1+deb11u1Fixed in 1.43.0-1+deb11u2Fixed in 1.52.0-1+deb12u2Fixed in 1.52.0-1+deb12u1Fixed in 1.64.0-1.1Fixed in 1.68.0-1
  42. Upgrade

    Upgrade debian/nginx to a version that resolves this vulnerability.

    Fixed in 1.18.0-6.1+deb11u3Fixed in 1.18.0-6.1+deb11u5Fixed in 1.22.1-9+deb12u3Fixed in 1.22.1-9+deb12u4Fixed in 1.26.3-3+deb13u1Fixed in 1.26.3-3+deb13u2Fixed in 1.28.2-2
  43. Upgrade

    Upgrade debian/nodejs to a version that resolves this vulnerability.

    Fixed in 12.22.12~dfsg-1~deb11u4Fixed in 12.22.12~dfsg-1~deb11u7Fixed in 18.20.4+dfsg-1~deb12u1Fixed in 20.19.2+dfsg-1Fixed in 22.22.0+dfsg+~cs22.19.6-1
  44. Upgrade

    Upgrade redhat/envoy to a version that resolves this vulnerability.

    Fixed in 1.11.1
  45. Upgrade

    Upgrade redhat/Nodejs to a version that resolves this vulnerability.

    Fixed in 8.16.1
  46. Upgrade

    Upgrade redhat/Nodejs to a version that resolves this vulnerability.

    Fixed in 10.16.3
  47. Upgrade

    Upgrade redhat/Nodejs to a version that resolves this vulnerability.

    Fixed in 12.8.1
  48. Upgrade

    Upgrade redhat/nginx to a version that resolves this vulnerability.

    Fixed in 1.16.1
  49. Upgrade

    Upgrade redhat/nginx to a version that resolves this vulnerability.

    Fixed in 1.17.3
  50. Upgrade

    Upgrade redhat/nghttp2 to a version that resolves this vulnerability.

    Fixed in 1.39.2
  51. Configuration

    For Red Hat Quay 3.0 (uses Nginx 1.12 from Red Hat Software Collections), edit the Nginx configuration (e.g., /mnt/quay/nginx/nginx.conf) to remove HTTP/2 support; as shown, run: sed -i 's/http2 //g' /mnt/quay/nginx/nginx.conf, using the host-mounted Nginx config copied from the quay container.

    Red Hat Quay (nginx within quay.io/redhat/quay:v3.0.3 container) HTTP/2 support in Nginx configuration (nginx.conf) = http2 disabled (remove http2)

Event History

Aug 1, 2019
Data Sourced
via Red Hat·11:34 AM
DescriptionSeverityAffected Software
Aug 13, 2019
CVE Published
05:00 PM
CVE Published
via MITRE·08:50 PM
Data Sourced
via MITRE·08:50 PM
DescriptionSeverityWeakness
Feb 23, 2026
Data Sourced
via Ubuntu·05:40 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·05:41 PM
DescriptionAffected Software
Data Sourced
via Launchpad·05:41 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2019-9513?

The severity of CVE-2019-9513 is critical due to its potential impact on system availability and resource exhaustion.

2

How do I fix CVE-2019-9513?

To fix CVE-2019-9513, you should upgrade to the latest versions of the affected software packages as specified in the security advisories.

3

What are the impacted products associated with CVE-2019-9513?

Products affected by CVE-2019-9513 include various versions of Apache HTTP Server, nghttp2, and several other software packages related to HTTP/2 implementation.

4

Who is affected by CVE-2019-9513?

Any systems utilizing affected versions of HTTP/2 implementations, especially in web server environments, are vulnerable to CVE-2019-9513.

5

Is there a workaround for CVE-2019-9513?

Currently, the recommended action is to apply the relevant patches, as there are no known effective workarounds for CVE-2019-9513.

Company

Resources

Contact

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