CVE-2018-1333: DoS for HTTP/2 connections by crafted requests

Published Jun 18, 2018
·
Updated

Apache httpd before version 2.4.34 has a vulnerability in the handling of specially crafted HTTP/2 requests, causing workers to be allocated 60 seconds longer than necessary, leading to worker exhaustion and a denial of service.

This issue only affects servers that have configured and enabled HTTP/2 support, which is not the default

External References:

https://httpd.apache.org/security/vulnerabilities24.html#CVE-2018-1333

Other sources

By specially crafting HTTP/2 requests, workers would be allocated 60 seconds longer than necessary, leading to worker exhaustion and a denial of service. Fixed in Apache HTTP Server 2.4.34 (Affected 2.4.18-2.4.30,2.4.33).

Launchpad

Affected Software

13 affected componentsFixes available
redhat/httpd<2.4.34
2.4.34
Apache HTTP Server>=2.4.18<=2.4.30
Apache HTTP Server=2.4.33
redhat JBoss Core Services=1.0
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
Canonical Ubuntu Linux=18.04
NetApp Cloud Backup
NetApp Storage Automation Store
All of the following
redhat JBoss Core Services=1.0
Any of the following
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
debian/apache2
2.4.62-1~deb11u12.4.66-1~deb11u12.4.66-1~deb12u12.4.62-1~deb12u22.4.66-1~deb13u12.4.66-6

Event History

Jun 18, 2018
CVE Published
via MITRE·06:00 PM
Data Sourced
via MITRE·06:00 PM
DescriptionWeakness
Data Sourced
via NVD·06:29 PM
DescriptionSeverityWeaknessAffected Software
Jul 20, 2018
Data Sourced
via Red Hat·04:49 AM
DescriptionSeverityAffected Software
Feb 20, 2026
Data Sourced
via Ubuntu·04:15 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Launchpad·04:16 PM
Description
Data Sourced
via Debian·04:16 PM
DescriptionAffected Software
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Frequently Asked Questions

1

What is CVE-2018-1333?

CVE-2018-1333 is a vulnerability that allows for worker exhaustion and denial of service by crafting specially-crafted HTTP/2 requests in Apache HTTP Server.

2

How severe is CVE-2018-1333?

CVE-2018-1333 has a severity rating of 7.5 (high).

3

Which software versions are affected by CVE-2018-1333?

Apache HTTP Server versions 2.4.18 to 2.4.30 and version 2.4.33 are affected by CVE-2018-1333.

4

How can CVE-2018-1333 be fixed?

CVE-2018-1333 can be fixed by upgrading to Apache HTTP Server version 2.4.34.

5

Where can I find more information about CVE-2018-1333?

More information about CVE-2018-1333 can be found at the following references: [Link 1](https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2018-1333), [Link 2](https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=1605049), [Link 3](https://httpd.apache.org/docs/2.4/mod/mod_http2.html).

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