CVE-2018-17189: Medium severity Apache HTTP Server vulnerability

Published Jan 22, 2019
·
Updated

A flaw was found in HTTP/2 (modhttp2) connections in Apache HTTP Server httpd 2.4.17 to 2.4.37. A DoS can be triggered by sending request bodies in a slow loris way to plain resources, the h2 stream for that request unnecessarily occupied a server thread cleaning up that incoming data.

References: https://seclists.org/oss-sec/2019/q1/80 https://httpd.apache.org/security/vulnerabilities24.html

Other sources

In Apache HTTP server versions 2.4.37 and prior, by sending request bodies in a slow loris way to plain resources, the h2 stream for that request unnecessarily occupied a server thread cleaning up that incoming data. This affects only HTTP/2 (modhttp2) connections.

Affected Software

63 affected componentsFixes available
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-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/httpd24<0:1.1-19.el6
0:1.1-19.el6
redhat/httpd24-httpd<0:2.4.34-15.el6
0:2.4.34-15.el6
redhat/httpd24-nghttp2<0:1.7.1-8.el6
0:1.7.1-8.el6
redhat/httpd24<0:1.1-19.el7
0:1.1-19.el7
redhat/httpd24-httpd<0:2.4.34-15.el7
0:2.4.34-15.el7
redhat/httpd24-nghttp2<0:1.7.1-8.el7
0:1.7.1-8.el7
debian/apache2<=2.4.25-3, <=2.4.37-1, <=2.4.25-3+deb9u6
2.4.38-12.4.25-3+deb9u7
Apache HTTP Server=2.4.17
Apache HTTP Server=2.4.18
Apache HTTP Server=2.4.20
Apache HTTP Server=2.4.23
Apache HTTP Server=2.4.25
Apache HTTP Server=2.4.26
Apache HTTP Server=2.4.27
Apache HTTP Server=2.4.28
Apache HTTP Server=2.4.29
Apache HTTP Server=2.4.30
Apache HTTP Server=2.4.33
Apache HTTP Server=2.4.34
Apache HTTP Server=2.4.35
Apache HTTP Server=2.4.37
NetApp Santricity Cloud Connector
NetApp Storage Automation Store
Fedoraproject Fedora=28
Fedoraproject Fedora=29
Debian Debian Linux=9.0
Oracle Enterprise Manager Ops Center=12.3.3
Oracle Hospitality Guest Access=4.2.0
Oracle Hospitality Guest Access=4.2.1
Oracle Instantis Enterprisetrack=17.1
Oracle Instantis Enterprisetrack=17.2
Oracle Instantis Enterprisetrack=17.3
Oracle Retail Xstore Point of Service=7.0
Oracle Retail Xstore Point of Service=7.1
Oracle Sun ZFS Storage Appliance Kit=8.8.6
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=18.10
All of the following
redhat JBoss Core Services=1.0
Any of the following
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
redhat JBoss Core Services=1.0
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
redhat/httpd<2.4.38
2.4.38
debian/apache2
2.4.62-1~deb11u12.4.67-1~deb11u32.4.68-1~deb12u12.4.67-1~deb12u32.4.68-1~deb13u12.4.67-1~deb13u32.4.68-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Fixed in 0:1.1-19.el6
  18. Upgrade

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

    Fixed in 0:2.4.34-15.el6
  19. Upgrade

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

    Fixed in 0:1.7.1-8.el6
  20. Upgrade

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

    Fixed in 0:1.1-19.el7
  21. Upgrade

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

    Fixed in 0:2.4.34-15.el7
  22. Upgrade

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

    Fixed in 0:1.7.1-8.el7
  23. Upgrade

    Upgrade debian/apache2 to a version that resolves this vulnerability.

    Fixed in 2.4.38-1Fixed in 2.4.25-3+deb9u7
  24. Upgrade

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

    Fixed in 2.4.38
  25. Upgrade

    Upgrade debian/apache2 to a version that resolves this vulnerability.

    Fixed in 2.4.62-1~deb11u1Fixed in 2.4.67-1~deb11u3Fixed in 2.4.68-1~deb12u1Fixed in 2.4.67-1~deb12u3Fixed in 2.4.68-1~deb13u1Fixed in 2.4.67-1~deb13u3Fixed in 2.4.68-1
  26. Upgrade

    Upgrade Apache HTTP Server httpd (mod_http2) to a version that resolves this vulnerability.

    Fixed in 2.4.38

Event History

Jan 22, 2019
CVE Published
12:00 AM
Data Sourced
via Red Hat·09:43 PM
DescriptionSeverityAffected Software
Jan 30, 2019
CVE Published
via MITRE·10:00 PM
Data Sourced
via MITRE·10:00 PM
DescriptionWeakness
Data Sourced
via NVD·10:29 PM
DescriptionSeverityWeaknessAffected Software
Sep 23, 2025
Data Sourced
via Ubuntu·04:32 AM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Launchpad·04:33 AM
Description
Jul 16, 2026
Data Sourced
via Debian·11:28 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2018-17189?

CVE-2018-17189 is classified as a DoS (Denial of Service) vulnerability.

2

How do I fix CVE-2018-17189?

To fix CVE-2018-17189, upgrade to version 2.4.38 or later of the Apache HTTP Server.

3

Which Apache HTTP Server versions are affected by CVE-2018-17189?

CVE-2018-17189 affects Apache HTTP Server versions 2.4.17 to 2.4.37.

4

What happens if my server is vulnerable to CVE-2018-17189?

If your server is vulnerable to CVE-2018-17189, it can be subjected to resource exhaustion due to slow loris attacks.

5

Is CVE-2018-17189 related to HTTP/2 connections?

Yes, CVE-2018-17189 specifically affects HTTP/2 connections in Apache HTTP Server.

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