Skip to content
Noroxi
CVE-2019-9513· NVD / CVE Program· CNA certcc

Some HTTP/2 implementations are vulnerable to resource loops, potentially leading to a denial of service

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.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Aug 13, 2019
Updated
Jun 16, 2026
EPSS
81.6% · 100th percentile
Follow this CVE

Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.

Report tools

JSON

Action score

54

Plan

Add it to your regular patch cycle.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
24 / 30 · 81.6%

CNA vs NVD score

NVD
7.5
CNA · certcc
7.5
agree

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

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Affected systems

VendorProduct
appleswiftnio
applemac os x
canonicalubuntu linux
apachetraffic server
debiandebian linux
fedoraprojectfedora
synologyskynas
synologydiskstation manager
synologyvs960hd firmware
synologyvs960hd
opensuseleap
redhatjboss core services

and 10 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • f5 nginx1.9.5 and later · before 1.16.1
  • f5 nginx1.17.0 and later · up to 1.17.2 inclusive
  • nodejs node.js8.0.0 and later · up to 8.8.1 inclusive
  • nodejs node.js8.9.0 and later · before 8.16.1
  • nodejs node.js10.0.0 and later · up to 10.12.0 inclusive
  • nodejs node.js10.13.0 and later · before 10.16.3
  • nodejs node.js12.0.0 and later · before 12.8.1

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8nginxbefore 1:1.14.1-9.module_el8.4.0+2221+af250afe.alma1:1.14.1-9.module_el8.4.0+2221+af250afe.alma
AlmaLinux:8nginxbefore 1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma
AlmaLinux:8nginxbefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-all-modulesbefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-filesystembefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-mod-http-image-filterbefore 1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma
AlmaLinux:8nginx-mod-http-image-filterbefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-mod-http-image-filterbefore 1:1.14.1-9.module_el8.4.0+2221+af250afe.alma1:1.14.1-9.module_el8.4.0+2221+af250afe.alma
AlmaLinux:8nginx-mod-http-perlbefore 1:1.14.1-9.module_el8.4.0+2221+af250afe.alma1:1.14.1-9.module_el8.4.0+2221+af250afe.alma
AlmaLinux:8nginx-mod-http-perlbefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-mod-http-perlbefore 1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma
AlmaLinux:8nginx-mod-http-xslt-filterbefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-mod-http-xslt-filterbefore 1:1.14.1-9.module_el8.4.0+2221+af250afe.alma1:1.14.1-9.module_el8.4.0+2221+af250afe.alma
AlmaLinux:8nginx-mod-http-xslt-filterbefore 1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma
AlmaLinux:8nginx-mod-mailbefore 1:1.14.1-9.module_el8.4.0+2221+af250afe.alma1:1.14.1-9.module_el8.4.0+2221+af250afe.alma
AlmaLinux:8nginx-mod-mailbefore 1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma
AlmaLinux:8nginx-mod-mailbefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-mod-streambefore 1:1.14.1-9.module_el8.3.0+2165+af250afe.alma1:1.14.1-9.module_el8.3.0+2165+af250afe.alma
AlmaLinux:8nginx-mod-streambefore 1:1.14.1-9.module_el8.4.0+2221+af250afe.alma1:1.14.1-9.module_el8.4.0+2221+af250afe.alma
AlmaLinux:8nginx-mod-streambefore 1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma
AlmaLinux:8nodejs-nodemonbefore 1.18.3-1.module_el8.3.0+2047+b07ac28e1.18.3-1.module_el8.3.0+2047+b07ac28e
AlmaLinux:8nodejs-nodemonbefore 1.18.3-1.module_el8.3.0+2023+d2377ea31.18.3-1.module_el8.3.0+2023+d2377ea3
AlmaLinux:8nodejs-packagingbefore 17-3.module_el8.4.0+2521+c668cc9f17-3.module_el8.4.0+2521+c668cc9f
AlmaLinux:8nodejs-packagingbefore 17-3.module_el8.3.0+2023+d2377ea317-3.module_el8.3.0+2023+d2377ea3

+96

Other highest-scoring records for the same primary product.

  • CVE-2019-9515Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a denial of service
    56Plan
  • CVE-2019-9514Some HTTP/2 implementations are vulnerable to a reset flood, potentially leading to a denial of service
    55Plan
  • CVE-2019-9512Some HTTP/2 implementations are vulnerable to ping floods, potentially leading to a denial of service
    55Plan
  • CVE-2019-9511Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service
    48Plan
  • CVE-2019-9516Some HTTP/2 implementations are vulnerable to a header leak, potentially leading to a denial of service
    43Plan
  • CVE-2018-4281In SwiftNIO before 1.8.0, a buffer overflow was addressed with improved size validation.
    39Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
AlmaLinux:nginx1:1.14.1-9.module_el8.5.0+34+dc1cfba5.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nginx-all-modules1:1.14.1-9.module_el8.3.0+2165+af250afe.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nginx-filesystem1:1.14.1-9.module_el8.3.0+2165+af250afe.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nginx-mod-http-image-filter1:1.14.1-9.module_el8.4.0+2221+af250afe.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nginx-mod-http-perl1:1.14.1-9.module_el8.4.0+2221+af250afe.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nginx-mod-http-xslt-filter1:1.14.1-9.module_el8.4.0+2221+af250afe.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nginx-mod-mail1:1.14.1-9.module_el8.4.0+2221+af250afe.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nginx-mod-stream1:1.14.1-9.module_el8.3.0+2165+af250afe.alma · AlmaLinux:8Package registry (OSV)
AlmaLinux:nodejs-nodemon1.18.3-1.module_el8.3.0+2023+d2377ea3 · AlmaLinux:8Package registry (OSV)
AlmaLinux:nodejs-packaging17-3.module_el8.4.0+2224+b07ac28e · AlmaLinux:8Package registry (OSV)
Alpine:nghttp21.39.2-r0 · Alpine:v3.10Package registry (OSV)
Alpine:nginx1.16.1-r0 · Alpine:v3.10Package registry (OSV)
Alpine:nodejs10.16.3-r0 · Alpine:v3.10Package registry (OSV)
Debian:nghttp21.39.2-1 · Debian:12Package registry (OSV)
Debian:nginx1.14.2-3 · Debian:12Package registry (OSV)
Debian:nodejs10.16.3~dfsg-1 · Debian:12Package registry (OSV)
openSUSE:nghttp21.39.2-lp151.3.3.1 · openSUSE:Leap 15.1Package registry (OSV)
openSUSE:nghttp2-python1.39.2-lp151.3.3.1 · openSUSE:Leap 15.1Package registry (OSV)
openSUSE:nginx1.14.2-lp151.4.3.1 · openSUSE:Leap 15.1Package registry (OSV)
openSUSE:nodejs1010.16.3-lp151.2.6.1 · openSUSE:Leap 15.0Package registry (OSV)
openSUSE:nodejs88.16.1-lp151.2.6.1 · openSUSE:Leap 15.0Package registry (OSV)
Red Hat:libnghttp20:1.33.0-1.el8_0.1 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
Red Hat:libnghttp2-debuginfo0:1.33.0-1.el8_0.1 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
Red Hat:libnghttp2-devel0:1.33.0-1.el8_0.1 · Red Hat:enterprise_linux:8::crbPackage registry (OSV)
Red Hat:nghttp20:1.33.0-1.el8_0.1 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
Red Hat:nghttp2-debuginfo0:1.33.0-1.el8_0.1 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
Red Hat:nghttp2-debugsource0:1.33.0-1.el8_0.1 · Red Hat:enterprise_linux:8::baseosPackage registry (OSV)
Red Hat:rh-nginx110-nginx1:1.10.2-9.el6.1 · Red Hat:rhel_software_collections:3::el6Package registry (OSV)
Red Hat:rh-nginx110-nginx-debuginfo1:1.10.2-9.el6.1 · Red Hat:rhel_software_collections:3::el6Package registry (OSV)
Red Hat:rh-nginx110-nginx-mod-http-image-filter1:1.10.2-9.el6.1 · Red Hat:rhel_software_collections:3::el6Package registry (OSV)

+11

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
function expand(node) {  return node.children.map(expand);}

Fixed

ts
const MAX_DEPTH = 32;function expand(node, depth = 0) {  if (depth > MAX_DEPTH) throw new Error("too deep");  return node.children.map((c) => expand(c, depth + 1));}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

All records