CVE-2018-16844

Name: CVE-2018-16844
Creator: NVD / NIST
Published: 2018-11-07T14:29:00.837+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 12.40%

Last modified Jun 17, 2026

CVE-2018-16844 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. nginx before versions 1.15.6 and 1.14.1 has a vulnerability in the implementation of HTTP/2 that can allow for excessive CPU usage. This issue affects nginx compiled with the ngx_http_v2_module (not compiled by default) if the 'http2' option of the 'listen' directive is used in a configuration file.. EPSS estimates a 12.40% chance of exploitation in the next 30 days.

Description

nginx before versions 1.15.6 and 1.14.1 has a vulnerability in the implementation of HTTP/2 that can allow for excessive CPU usage. This issue affects nginx compiled with the ngx_http_v2_module (not compiled by default) if the 'http2' option of the 'listen' directive is used in a configuration file.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

12.40%

95.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
F5	Nginx	>= 1.9.5, < 1.14.1
F5	Nginx	>= 1.15.0, < 1.15.6
Debian	Debian Linux	9.0
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	18.10
Apple	Xcode	< 13.0

References

http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00035.htmlThird Party Advisory
http://mailman.nginx.org/pipermail/nginx-announce/2018/000220.htmlMailing List, Vendor Advisory
http://seclists.org/fulldisclosure/2021/Sep/36Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/105868Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1042038Third Party Advisory, VDB Entry
https://access.redhat.com/errata/RHSA-2018:3680Third Party Advisory
https://access.redhat.com/errata/RHSA-2018:3681Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16844Issue Tracking
https://support.apple.com/kb/HT212818Third Party Advisory
https://usn.ubuntu.com/3812-1/Third Party Advisory
https://www.debian.org/security/2018/dsa-4335Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00035.htmlThird Party Advisory
http://mailman.nginx.org/pipermail/nginx-announce/2018/000220.htmlMailing List, Vendor Advisory
http://seclists.org/fulldisclosure/2021/Sep/36Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/105868Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1042038Third Party Advisory, VDB Entry
https://access.redhat.com/errata/RHSA-2018:3680Third Party Advisory
https://access.redhat.com/errata/RHSA-2018:3681Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16844Issue Tracking
https://support.apple.com/kb/HT212818Third Party Advisory
https://usn.ubuntu.com/3812-1/Third Party Advisory
https://www.debian.org/security/2018/dsa-4335Third Party Advisory

Timeline

Published: Nov 7, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-16844?

How severe is CVE-2018-16844?

CVE-2018-16844 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 12.40% probability of exploitation in the next 30 days.

How do I fix CVE-2018-16844?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-16844?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST