CVE-2019-9518: Some HTTP/2 implementations are vulnerable to a flood of empty frames, potentially leading to a denial of service

Published Aug 1, 2019
·
Updated

A flaw was found in HTTP/2. Using frames with an empty payload, a flood could occur that results in excessive CPU usage and starvation of other clients. The highest threat from this vulnerability is to system availability.

Other sources

HTTP/2 flood using frames with an empty payload that results in excessive CPU usage and starvation of other clients.

— Red Hat

Netflix has discovered several resource exhaustion vectors affecting a variety of third-party HTTP/2 implementations. These attack vectors can be used to launch DoS attacks against servers that support HTTP/2 communication. Netflix worked with Google and CERT/CC to coordinate disclosure to the Internet community.

— Node.Js

Some HTTP/2 implementations are vulnerable to a flood of empty frames, potentially leading to a denial of service. The attacker sends a stream of frames with an empty payload and without the end-of-stream flag. These frames can be DATA, HEADERS, CONTINUATION and/or PUSHPROMISE. The peer spends time processing each frame disproportionate to attack bandwidth. This can consume excess CPU.

Affected Software

57 affected componentsFixes available
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/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
debian/trafficserver
8.1.10+ds-1~deb11u18.1.11+ds-0+deb11u29.2.5+ds-0+deb12u19.2.5+ds-0+deb12u29.2.5+ds-1
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
Synology Skynas
Synology DiskStation Manager=6.2
All of the following
Synology Vs960hd Firmware
Synology Vs960hd
Fedoraproject Fedora=29
Fedoraproject Fedora=30
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
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
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/undertow<2.0.26.
2.0.26.
Node.js Node.js>=8.0.0<8.16.1, >=10.0.0<10.16.3, >=12.0.0<12.8.1
8.16.110.16.312.8.1
Node.js Node.js>=10.0.0<10.16.3
10.16.3
Node.js Node.js>=12.0.0<12.8.1
12.8.1
Node.js Node.js>=8.0.0<8.16.1
8.16.1
All of the following
Apple Swiftnio>=1.0.0<=1.4.0
Canonical Ubuntu Linux>=14.04

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

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

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

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

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

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

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

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

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

    Fixed in 8.1.10+ds-1~deb11u1Fixed in 8.1.11+ds-0+deb11u2Fixed in 9.2.5+ds-0+deb12u1Fixed in 9.2.5+ds-0+deb12u2Fixed in 9.2.5+ds-1
  6. Upgrade

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

    Fixed in 1.11.1
  7. Upgrade

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

    Fixed in 8.16.1
  8. Upgrade

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

    Fixed in 10.16.3
  9. Upgrade

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

    Fixed in 12.8.1
  10. Upgrade

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

    Fixed in 2.0.26.
  11. Upgrade

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

    Fixed in 2.0.27.
  12. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.16.1Fixed in 10.16.3Fixed in 12.8.1
  13. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.16.3
  14. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 12.8.1
  15. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.16.1

Event History

Aug 1, 2019
Data Sourced
via Red Hat·11:49 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
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software
Aug 15, 2019
Data Sourced
via Node.js·12:00 AM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2019-9518?

CVE-2019-9518 is a vulnerability in HTTP/2 that allows for a flood of empty frames, potentially leading to a denial of service.

2

What is the severity of CVE-2019-9518?

CVE-2019-9518 has a severity level of high, with a severity value of 7.

3

Which software is affected by CVE-2019-9518?

The affected software includes rh-nodejs10, rh-nodejs10-nodejs, rh-nodejs8, rh-nodejs8-nodejs, envoy, Nodejs, undertow, netty, and trafficserver.

4

How can CVE-2019-9518 be fixed?

To fix CVE-2019-9518, ensure that you have the latest versions of the affected software installed, as specified in the Remediation section of the references.

5

Where can I find more information about CVE-2019-9518?

You can find more information about CVE-2019-9518 in the references provided.

Company

Resources

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