Description
The stream_reqbody_cl function in mod_proxy_http.c in the mod_proxy module in the Apache HTTP Server before 2.3.3, when a reverse proxy is configured, does not properly handle an amount of streamed data that exceeds the Content-Length value, which allows remote attackers to cause a denial of service (CPU consumption) via crafted requests.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | apache2 | 2.2.11-7 | — |
| Debian 13 | apache2 | 2.2.11-7 | — |
| Debian 12 | apache2 | 2.2.11-7 | — |
| Debian 5.0 | apache2 | 2.2.9-10+lenny4 | DSA-1834-1 |
| Debian 4.0 | apache2 | 2.2.3-4+etch9 | DSA-1834-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | httpd +2 | 2.2.3-22.el5_3.2 | RHSA-2009:1148 |
| RHEL 5 | mod_ssl | 1:2.2.3-22.el5_3.2 | RHSA-2009:1148 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Rhel Application Stack 2 | httpd +2 | 2.2.11-3.el5s2 | RHSA-2009:1156 |
| Red Hat Rhel Application Stack 2 | mod_ssl | 1:2.2.11-3.el5s2 | RHSA-2009:1156 |
| Red Hat JBoss Web Server 1 | httpd +2 | 2.2.10-10.ep5.el5 | RHSA-2009:1155 |
| Red Hat JBoss Web Server 1 | httpd22 +5 | 2.2.10-23.1.ep5.el4 | RHSA-2009:1160 |
| Red Hat JBoss Web Server 1 | mod_ssl | 1:2.2.10-10.ep5.el5 | RHSA-2009:1155 |
| Red Hat JBoss Web Server 1 | mod_ssl22 | 1:2.2.10-23.1.ep5.el4 | RHSA-2009:1160 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | apache2 | 2.4.23-4.1 | openSUSE-SU-2024:10268-1 |
Advisories 6
- RHSA-2009:1148 Red Hat Security Advisory: httpd security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-1834-1 apache2 apache2-mpm-itk - denial of service Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10268-1 apache2-2.4.23-4.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- RHSA-2009:1160 Red Hat Security Advisory: httpd22 security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2009:1156 Red Hat Security Advisory: httpd security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2009:1155 Red Hat Security Advisory: httpd security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
References
- FEDORA-2009-8812 vendor-advisory
- SUSE-SA:2009:050 vendor-advisory
- PK99480 vendor-advisory
- 55553 vdb-entry
- PK91259 vendor-advisory
- oval:org.mitre.oval:def:12330 vdb-entry signature
- MDVSA-2009:149 vendor-advisory
- RHSA-2009:1156 vendor-advisory
- 35865 third-party-advisory
- 1022509 vdb-entry
- 37152 third-party-advisory
- http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/proxy/mod_proxy_http.c?r1=790587&r2=790586&pathrev=790587
- http://svn.apache.org/viewvc/httpd/httpd/trunk/CHANGES?revision=790587
- 35691 third-party-advisory
- http://svn.apache.org/viewvc?view=rev&revision=790587
- 20091112 rPSA-2009-0142-1 httpd mod_ssl mailing-list
- 35565 vdb-entry
- DSA-1834 vendor-advisory
- 20091113 rPSA-2009-0142-2 httpd mod_ssl mailing-list
- HPSBUX02612 vendor-advisory
- http://www.oracle.com/technetwork/topics/security/cpuapr2013-1899555.html
- oval:org.mitre.oval:def:9403 vdb-entry signature
- http://svn.apache.org/viewvc/httpd/httpd/trunk/CHANGES?r1=790587&r2=790586&pathrev=790587
- GLSA-200907-04 vendor-advisory
- http://wiki.rpath.com/Advisories:rPSA-2009-0142
- RHSA-2009:1148 vendor-advisory
- oval:org.mitre.oval:def:8616 vdb-entry signature
- USN-802-1 vendor-advisory
- 37221 third-party-advisory
- ADV-2009-3184 vdb-entry
- 35793 third-party-advisory
- APPLE-SA-2009-11-09-1 vendor-advisory
- MDVSA-2013:150 vendor-advisory
- 35721 third-party-advisory
- http://support.apple.com/kb/HT3937
- [httpd-cvs] 20190815 svn commit: r1048743 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilit mailing-list
- [httpd-cvs] 20190815 svn commit: r1048742 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilit mailing-list
- [httpd-cvs] 20200401 svn commit: r1058586 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilit mailing-list
- [httpd-cvs] 20200401 svn commit: r1058587 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/vulnerabilities-httpd.xml security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilit mailing-list
- [httpd-cvs] 20210330 svn commit: r1073139 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1888194 [5/13] - /httpd/site/trunk/content/security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1073140 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/cvejsontohtml.py security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabilities_24.ht mailing-list
- [httpd-cvs] 20210330 svn commit: r1073139 [5/13] - in /websites/staging/httpd/trunk/content: ./ security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1073146 [2/3] - in /websites/staging/httpd/trunk/content: ./ security/cvejsontohtml.py security/vulnerabilities-httpd.xml security/vulnerabilities_22.html security/vulnerabilities_24.html mailing-list
- [httpd-cvs] 20210330 svn commit: r1073149 [1/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/ mailing-list
- [httpd-cvs] 20210330 svn commit: r1073149 [6/13] - in /websites/staging/httpd/trunk/content: ./ security/ security/json/ mailing-list
- [httpd-cvs] 20210603 svn commit: r1075360 [2/3] - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2021-31618.json security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabiliti mailing-list
- [httpd-cvs] 20210606 svn commit: r1075470 [3/4] - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2020-13938.json security/vulnerabilities_13.html security/vulnerabilities_20.html security/vulnerabilities_22.html security/vulnerabiliti mailing-list
- [mina-users] 20210714 CWE-189 CWE-189 Numeric Errors: CVE-2009-1890 in Apache Mina SSHD SFTP 2.7.0 library mailing-list