Vulnerabilities
Misconfiguration
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CVE Vulnerabilities

CVE-2009-1955

Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')

Published: Jun 08, 2009 | Modified: Apr 09, 2025
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P
RedHat/V2
5 MODERATE
AV:N/AC:L/Au:N/C:N/I:N/A:P
RedHat/V3
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2009-1955
CWEhttps://cwe.mitre.org/data/definitions/776.html

The expat XML parser in the apr_xml_* interface in xml/apr_xml.c in Apache APR-util before 1.3.7, as used in the mod_dav and mod_dav_svn modules in the Apache HTTP Server, allows remote attackers to cause a denial of service (memory consumption) via a crafted XML document containing a large number of nested entity references, as demonstrated by a PROPFIND request, a similar issue to CVE-2003-1564.

Weakness

The product uses XML documents and allows their structure to be defined with a Document Type Definition (DTD), but it does not properly control the number of recursive definitions of entities.

Affected Software

NameVendorStart VersionEnd Version
Apr-utilApache*1.3.7 (excluding)
JBEWS 1.0 for RHEL 4RedHathttpd22-0:2.2.10-23.1.ep5.el4*
Red Hat Certificate System 7.3RedHatant-0:1.6.5-1jpp_1rh*
Red Hat Certificate System 7.3RedHatavalon-logkit-0:1.2-2jpp_4rh*
Red Hat Certificate System 7.3RedHataxis-0:1.2.1-1jpp_3rh*
Red Hat Certificate System 7.3RedHatclasspathx-jaf-0:1.0-2jpp_6rh*
Red Hat Certificate System 7.3RedHatclasspathx-mail-0:1.1.1-2jpp_8rh*
Red Hat Certificate System 7.3RedHatgeronimo-specs-0:1.0-0.M4.1jpp_10rh*
Red Hat Certificate System 7.3RedHatjakarta-commons-modeler-0:2.0-3jpp_2rh*
Red Hat Certificate System 7.3RedHatlog4j-0:1.2.12-1jpp_1rh*
Red Hat Certificate System 7.3RedHatmx4j-1:3.0.1-1jpp_4rh*
Red Hat Certificate System 7.3RedHatpcsc-lite-0:1.3.3-3.el4*
Red Hat Certificate System 7.3RedHatrhpki-ca-0:7.3.0-20.el4*
Red Hat Certificate System 7.3RedHatrhpki-java-tools-0:7.3.0-10.el4*
Red Hat Certificate System 7.3RedHatrhpki-kra-0:7.3.0-14.el4*
Red Hat Certificate System 7.3RedHatrhpki-manage-0:7.3.0-19.el4*
Red Hat Certificate System 7.3RedHatrhpki-native-tools-0:7.3.0-6.el4*
Red Hat Certificate System 7.3RedHatrhpki-ocsp-0:7.3.0-13.el4*
Red Hat Certificate System 7.3RedHatrhpki-tks-0:7.3.0-13.el4*
Red Hat Certificate System 7.3RedHattomcat5-0:5.5.23-0jpp_4rh.16*
Red Hat Certificate System 7.3RedHatxerces-j2-0:2.7.1-1jpp_1rh*
Red Hat Certificate System 7.3RedHatxml-commons-0:1.3.02-2jpp_1rh*
Red Hat Enterprise Linux 3RedHathttpd-0:2.0.46-73.ent*
Red Hat Enterprise Linux 4RedHatapr-util-0:0.9.4-22.el4_8.1*
Red Hat Enterprise Linux 5RedHatapr-util-0:1.2.7-7.el5_3.1*
Apache2Ubuntudapper*
Apr-utilUbuntuhardy*
Apr-utilUbuntuintrepid*
Apr-utilUbuntujaunty*
Apr-utilUbuntuupstream*

Potential Mitigations

References

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