CVE-2019-9518

30

FAUCET Score

CVE-2019-9518 is a denial-of-service vulnerability affecting various HTTP/2 implementations, including those from Apache, Apple, Node.js, and Oracle. Attackers can flood a server with empty HTTP/2 frames, consuming excessive CPU resources. This vulnerability has a CVSS score of 7.5 (High) due to its network-based attack vector and low attack complexity, potentially leading to a complete denial of service. While there is no known active exploitation or public exploit code (Metasploit, Nuclei, ExploitDB), the vulnerability has garnered significant community discussion and media coverage, indicating awareness within the cybersecurity landscape.

Impacted Technologies

Vendor	Product	Version(s)	CPE
		>= 1.0.0, <= 1.4.0CPE matchmatch criteria	cpe:2.3:a:apple:swiftnio::::::::
		>= 6.0.0, <= 6.2.3CPE matchmatch criteria	cpe:2.3:a:apache:traffic_server::::::::
		>= 7.0.0, <= 7.1.6CPE matchmatch criteria	cpe:2.3:a:apache:traffic_server::::::::
		>= 8.0.0, <= 8.0.3CPE matchmatch criteria	cpe:2.3:a:apache:traffic_server::::::::
		16.04CPE matchmatch criteria	cpe:2.3:o:canonical:ubuntu_linux:16.04::::lts:::

CVSS Data

CVSS version used by this source: 3.0

7.5HIGH

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

Exploitability Score

3.9

Impact Score

3.6

CvssVersion

3.0

Exploit Intelligence

EPSS Score

25.45%

Probability of exploitation in next 30 days

EPSS Percentile

97.7%

Percentile rank of EPSS score among Peer Group

As of 2026-07-27

Model: v2026.06.15

This CVE's current EPSS score of 0.2545 is in the 96th percentile among its peer group of 51,551 CVEs.

Social Chatter

No social media mentions found for this CVE.

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (53)

microsoftpatch availablevia msrc

Product: Windows Server 2016 (Server Core installation)

microsoftpatch availablevia msrc

Product: Windows Server 2016

microsoftpatch availablevia msrc

Product: Windows 10 Version 1607 for x64-based Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1607 for 32-bit Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1703 for 32-bit Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1703 for x64-based Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1803 for 32-bit Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1803 for x64-based Systems

microsoftpatch availablevia msrc

Product: Windows Server, version 1803 (Server Core Installation)

microsoftpatch availablevia msrc

Product: Windows 10 Version 1803 for ARM64-based Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1809 for 32-bit Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1809 for x64-based Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1809 for ARM64-based Systems

microsoftpatch availablevia msrc

Product: Windows Server 2019

microsoftpatch availablevia msrc

Product: Windows Server 2019 (Server Core installation)

microsoftpatch availablevia msrc

Product: Windows 10 Version 1709 for 32-bit Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1709 for x64-based Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1709 for ARM64-based Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1903 for 32-bit Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1903 for x64-based Systems

microsoftpatch availablevia msrc

Product: Windows 10 Version 1903 for ARM64-based Systems

microsoftpatch availablevia msrc

Product: Windows Server, version 1903 (Server Core installation)

microsoftpatch availablevia msrc

Product: Windows 10 for 32-bit Systems

microsoftpatch availablevia msrc

Product: Windows 10 for x64-based Systems

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSFixed in: rh-nodejs8-nodejs-0:8.16.1-2.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUSFixed in: rh-nodejs8-nodejs-0:8.16.1-2.el7

redhatpatch availablevia redhat_api

Product: Red Hat AMQ 7.4.3

redhatpatch availablevia redhat_api

Product: Red Hat Data Grid 7.3.3Fixed in: netty

redhatpatch availablevia redhat_api

Product: Red Hat Decision Manager 7Fixed in: netty

redhatpatch availablevia redhat_api

Product: Red Hat Enterprise Linux 8Fixed in: nodejs:10-8000020190911085529.f8e95b4e

redhatpatch availablevia redhat_api

Product: Red Hat Fuse 6.3Fixed in: netty

redhatpatch availablevia redhat_api

Product: Red Hat Fuse 7.5.0Fixed in: netty

redhatpatch availablevia redhat_api

Product: Red Hat Fuse 7.6.0Fixed in: undertow

redhatpatch availablevia redhat_api

Product: Red Hat Process Automation 7Fixed in: netty

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7Fixed in: rh-nodejs10-0:3.2-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7Fixed in: rh-nodejs10-nodejs-0:10.16.3-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7Fixed in: rh-nodejs8-0:3.0-5.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7Fixed in: rh-nodejs8-nodejs-0:8.16.1-2.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUSFixed in: rh-nodejs10-0:3.2-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUSFixed in: rh-nodejs10-nodejs-0:10.16.3-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUSFixed in: rh-nodejs8-0:3.0-5.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUSFixed in: rh-nodejs8-nodejs-0:8.16.1-2.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUSFixed in: rh-nodejs10-0:3.2-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUSFixed in: rh-nodejs10-nodejs-0:10.16.3-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUSFixed in: rh-nodejs8-0:3.0-5.el7

redhatpatch availablevia redhat_api

Product: Red Hat AMQ

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSFixed in: rh-nodejs10-0:3.2-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSFixed in: rh-nodejs10-nodejs-0:10.16.3-3.el7

redhatpatch availablevia redhat_api

Product: Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSFixed in: rh-nodejs8-0:3.0-5.el7

redhatvendor investigatingvia redhat_api

Product: Red Hat JBoss Enterprise Application Platform 7Fixed in: undertow-core

redhatno patchvia redhat_api

Product: Red Hat OpenShift Application RuntimesFixed in: netty

redhatno patchvia redhat_api

Product: Red Hat AMQ Broker 7Fixed in: netty

redhatno patchvia redhat_api

Product: Red Hat AMQ Broker 7Fixed in: jetty

Vendor Advisories (2)

redhatCVE-2019-9518Important

HTTP/2: flood using empty frames results in excessive resource consumption

microsoft2019-Aug/CVE-2019-9518Important

HTTP/2 Server Denial of Service Vulnerability

References

lists.opensuse.org / opensuse-security-announce/2019-09/msg00031.html

Mailing ListThird Party Advisory

lists.opensuse.org / opensuse-security-announce/2019-09/msg00032.html

Mailing ListThird Party Advisory

access.redhat.com / errata/RHSA-2019:2925

Third Party Advisory

access.redhat.com / errata/RHSA-2019:2939

Third Party Advisory

access.redhat.com / errata/RHSA-2019:2955

Third Party Advisory

access.redhat.com / errata/RHSA-2019:3892

Third Party Advisory

access.redhat.com / errata/RHSA-2019:4352

Third Party Advisory

access.redhat.com / errata/RHSA-2020:0727

Third Party Advisory

seclists.org / fulldisclosure/2019/Aug/16

Mailing ListThird Party Advisory

github.com / Netflix/security-bulletins/blob/master/advisories/third-party/2019-002.md

Third Party Advisory

kb.cert.org / vuls/id/605641

Third Party AdvisoryUS Government Resource

kc.mcafee.com / corporate/index

Third Party Advisory

lists.apache.org / thread.html/091b518265bce56a16af87b77c8cfacda902a02079e866f9fdf13b61%40%3Cusers.trafficserver.apache.org%3E

lists.apache.org / thread.html/2653c56545573b528f3f6352a29eccaf498bd6fb2a6a59568d81a61d%40%3Cannounce.trafficserver.apache.org%3E

lists.apache.org / thread.html/9317fd092b257a0815434b116a8af8daea6e920b6673f4fd5583d5fe%40%3Ccommits.druid.apache.org%3E

lists.apache.org / thread.html/ff5b0821a6985159a832ff6d1a4bd311ac07ecc7db1e2d8bab619107%40%3Cdev.trafficserver.apache.org%3E

lists.apache.org / thread.html/r99a625fb17032646d96cd23dec49603ff630e9318e44a686d63046bc%40%3Ccommits.cassandra.apache.org%3E

lists.apache.org / thread.html/rd31230d01fa6aad18bdadc0720acd1747e53690bd35f73a48e7a9b75%40%3Ccommits.cassandra.apache.org%3E

lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/4ZQGHE3WTYLYAYJEIDJVF2FIGQTAYPMC

lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/CMNFX5MNYRWWIMO4BTKYQCGUDMHO3AXP

seclists.org / bugtraq/2019/Aug/24

Mailing ListThird Party Advisory

seclists.org / bugtraq/2019/Sep/18

Mailing ListThird Party Advisory

security.netapp.com / advisory/ntap-20190823-0005

Third Party Advisory

support.f5.com / csp/article/K46011592

Third Party Advisory

support.f5.com / csp/article/K46011592

debian.org / security/2019/dsa-4520

Third Party Advisory

synology.com / security/advisory/Synology_SA_19_33

Third Party Advisory