CVE-2009-1891: High severity Apache HTTP Server vulnerability

Published Jul 1, 2009
·
Updated

François Guerraz reported in Debian BTS a possible DoS (CPU consumption) a DoS with moddeflate since it does not stop to compress large files even after the network connection has been closed. This allows to use large amounts of CPU if there is a largish file available that has moddeflate enabled.

Original report: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=534712

Post to the apache-httpd-dev mailing list: http://marc.info/?l=apache-httpd-dev&m=124621326524824&w=2

Other sources

The moddeflate module in Apache httpd 2.2.11 and earlier compresses large files until completion even after the associated network connection is closed, which allows remote attackers to cause a denial of service (CPU consumption).

Affected Software

15 affected components
Apache HTTP Server>=2.0.35<2.0.64
Apache HTTP Server>=2.2.0<2.2.12
Debian Debian Linux=5.0
Debian Debian Linux=4.0
Debian Debian Linux=6.0
Fedoraproject Fedora=11
Canonical Ubuntu Linux=9.04
Canonical Ubuntu Linux=8.10
Canonical Ubuntu Linux=8.04
Canonical Ubuntu Linux=6.06
redhat Enterprise Linux Server=5.0
redhat Enterprise Linux Workstation=5.0
redhat Enterprise Linux Desktop=5.0
redhat Enterprise Linux Server Aus=5.3
redhat Enterprise Linux Eus=5.3

Event History

Jul 1, 2009
Data Sourced
01:30 PM
DescriptionSeverityAffected Software
Jul 10, 2009
CVE Published
via MITRE·03:00 PM
Data Sourced
via MITRE·03:00 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2009-1891?

CVE-2009-1891 is classified as a denial of service (DoS) vulnerability due to excessive CPU consumption.

2

How do I fix CVE-2009-1891?

To mitigate CVE-2009-1891, it is recommended to upgrade Apache HTTP Server to a version beyond 2.0.64 or 2.2.12.

3

What versions of Apache HTTP Server are affected by CVE-2009-1891?

CVE-2009-1891 affects Apache HTTP Server versions between 2.0.35 and 2.0.64, as well as 2.2.0 to 2.2.12.

4

Can CVE-2009-1891 be exploited on Debian systems?

Yes, CVE-2009-1891 can be exploited on Debian systems running affected versions of the Apache HTTP Server.

5

Is CVE-2009-1891 specific to certain operating systems?

CVE-2009-1891 primarily affects Apache HTTP Server installations on Debian, Fedora, and Ubuntu operating systems.

Contact

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