CVE-2009-3720

Summary

CVECVE-2009-3720
StatePUBLISHED
Assignerredhat
Source PriorityCVE Program / NVD first with legacy fallback
Published2009-11-03 16:30:12 UTC
Updated2026-07-20 14:35:41 UTC
DescriptionThe updatePosition function in lib/xmltok_impl.c in libexpat in Expat 2.0.1, as used in Python, PyXML, w3c-libwww, and other software, allows context-dependent attackers to cause a denial of service (application crash) via an XML document with crafted UTF-8 sequences that trigger a buffer over-read, a different vulnerability than CVE-2009-2625.

Risk And Classification

Primary CVSS: v2.0 5 from [email protected]

AV:N/AC:L/Au:N/C:N/I:N/A:P

Problem Types: NVD-CWE-noinfo | n/a

CVSS v2.0 Breakdown

Access Vector
Network
Access Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial

AV:N/AC:L/Au:N/C:N/I:N/A:P

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Apache Http Server All All All All
Application Libexpat Project Libexpat 2.0.1 All All All
Application Python Python All All All All
Application Python Pyxml All All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Na N/a affected n/a Not specified

References

ReferenceSourceLinkTags
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Red Hat update for 4Suite - Secunia.com af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
[security-announce] SUSE Security Summary Report: SUSE-SR:2010:013 af854a3a-2127-422b-91ae-364da2661108 lists.opensuse.org Third Party Advisory, VDB Entry
[security-announce] SUSE Security Summary Report: SUSE-SR:2010:014 af854a3a-2127-422b-91ae-364da2661108 lists.opensuse.org Third Party Advisory, VDB Entry
Webmail : Solution de messagerie professionnelle - OVHcloud- OVH af854a3a-2127-422b-91ae-364da2661108 www.vupen.com Broken Link
oss-security - Re: CVE Request -- expat [was: Re: Regarding expat bug 1990430] af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
[SECURITY] Fedora 10 Update: expat-2.0.1-8.fc10 af854a3a-2127-422b-91ae-364da2661108 www.redhat.com Third Party Advisory
Support / Security / Advisories / / MDVSA-2009:216 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Broken Link
VMware ESX Server Multiple Vulnerabilities - Advisories - Community af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Apache APR-util Multiple Denial of Service Vulnerabilities - Advisories - Community af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
[security-announce] SUSE Security Summary Report: SUSE-SR:2010:012 af854a3a-2127-422b-91ae-364da2661108 lists.opensuse.org Third Party Advisory, VDB Entry
Ubuntu update for expat - Secunia Advisories - Vulnerability Information - Secunia.com af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
[SECURITY] Fedora 12 Update: expat-2.0.1-8.fc12 af854a3a-2127-422b-91ae-364da2661108 www.redhat.com Third Party Advisory
About Secunia Research | Flexera af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Ubuntu update for cmake - Advisories - Community af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Webmail : Solution de messagerie professionnelle - OVHcloud- OVH af854a3a-2127-422b-91ae-364da2661108 www.vupen.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Support / Security / Advisories / / MDVSA-2009:211 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Permissions Required, Third Party Advisory
About Secunia Research | Flexera af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Support af854a3a-2127-422b-91ae-364da2661108 www.redhat.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Expat XML Parser / Bugs / #464 Parser crash with specially formatted UTF-8 sequences af854a3a-2127-422b-91ae-364da2661108 sourceforge.net Mailing List, Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Repository / Oval Repository af854a3a-2127-422b-91ae-364da2661108 oval.cisecurity.org Broken Link
VMware vMA Update for Multiple Packages - Advisories - Community af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
oss-security - Re: Re: expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
Webmail : Solution de messagerie professionnelle - OVHcloud- OVH af854a3a-2127-422b-91ae-364da2661108 www.vupen.com Broken Link
oss-security - Re: Regarding expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
expat UTF-8 Sequence Parsing Flaw Lets Users Deny Service - SecurityTracker af854a3a-2127-422b-91ae-364da2661108 www.securitytracker.com Third Party Advisory, VDB Entry
Gentoo Bug 280615 - <dev-libs/expat-2.0.1-r2 Bug 1990430 UTF-8 parser crash (CVE-2009-2625?) af854a3a-2127-422b-91ae-364da2661108 bugs.gentoo.org Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
oss-security - Re: CVE Request -- expat [was: Re: Regarding expat bug 1990430] af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
oss-security - Re: Re: Regarding expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
[security-announce] SUSE Security Summary Report: SUSE-SR:2009:018 af854a3a-2127-422b-91ae-364da2661108 lists.opensuse.org Third Party Advisory
[SECURITY] Fedora 14 Update: udunits2-2.1.19-1.fc14 af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Third Party Advisory
sunsolve.sun.com/search/document.do af854a3a-2127-422b-91ae-364da2661108 sunsolve.sun.com Broken Link
Webmail : Solution de messagerie professionnelle - OVHcloud- OVH af854a3a-2127-422b-91ae-364da2661108 www.vupen.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Support / Security / Advisories / / MDVSA-2009:218 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Webmail : Solution de messagerie professionnelle - OVHcloud- OVH af854a3a-2127-422b-91ae-364da2661108 www.vupen.com Broken Link
Red Hat Customer Portal af854a3a-2127-422b-91ae-364da2661108 www.redhat.com Broken Link
[SECURITY] Fedora 14 Update: libtlen-0-0.10.20060309.fc14 af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Third Party Advisory
The Slackware Linux Project: Slackware Security Advisories af854a3a-2127-422b-91ae-364da2661108 slackware.com Mailing List, Third Party Advisory
Red Hat update for PyXML - Secunia.com af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
[SECURITY] Fedora 12 Update: PyXML-0.8.4-17.fc12 af854a3a-2127-422b-91ae-364da2661108 www.redhat.com Third Party Advisory
404 Not Found af854a3a-2127-422b-91ae-364da2661108 svn.python.org Permissions Required, Third Party Advisory
Support / Security / Advisories / / MDVSA-2009:215 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Broken Link
Fedora update for udunits2 - Advisories - Community af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Support / Security / Advisories / / MDVSA-2009:219 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Broken Link
oss-security - Re: CVE Request -- expat [was: Re: Regarding expat bug 1990430] af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
[Expat-bugs] [ expat-Bugs-1990430 ] Parser crash with specially formatted UTF-8 sequences af854a3a-2127-422b-91ae-364da2661108 mail.python.org Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
CVS Info for project expat af854a3a-2127-422b-91ae-364da2661108 expat.cvs.sourceforge.net Mailing List, Third Party Advisory
oss-security - Re: expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
Repository / Oval Repository af854a3a-2127-422b-91ae-364da2661108 oval.cisecurity.org Broken Link
[Security-announce] VMSA-2010-0004 ESX Service Console and vMA third party updates af854a3a-2127-422b-91ae-364da2661108 lists.vmware.com Broken Link
USN-890-6: CMake vulnerabilities | Ubuntu af854a3a-2127-422b-91ae-364da2661108 www.ubuntu.com Third Party Advisory
Support / Security / Advisories / / MDVSA-2009:212 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Broken Link
VMware ESX Server 4 Multiple Vulnerabilities - Advisories - Community af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
oss-security - Re: Re: expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
[security-announce] SUSE Security Summary Report: SUSE-SR:2010:011 af854a3a-2127-422b-91ae-364da2661108 lists.opensuse.org Third Party Advisory, VDB Entry
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Support / Security / Advisories / / MDVSA-2009:217 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Broken Link
Support / Security / Advisories / / MDVSA-2009:220 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Broken Link
oss-security - expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
Bug 531697 – CVE-2009-3720 expat: buffer over-read and crash on XML with malformed UTF-8 sequences af854a3a-2127-422b-91ae-364da2661108 bugzilla.redhat.com Issue Tracking
CVS Info for project expat af854a3a-2127-422b-91ae-364da2661108 expat.cvs.sourceforge.net Exploit
[SECURITY] Fedora 12 Update: libtlen-0-0.10.20060309.fc12 af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Third Party Advisory
'[security bulletin] HPSBUX02645 SSRT100387 rev.1 - HP-UX Apache Web Server, Remote Information Discl' - MARC af854a3a-2127-422b-91ae-364da2661108 marc.info Mailing List, Third Party Advisory
Webmail : Solution de messagerie professionnelle - OVHcloud- OVH af854a3a-2127-422b-91ae-364da2661108 www.vupen.com Broken Link
Webmail : Solution de messagerie professionnelle - OVHcloud- OVH af854a3a-2127-422b-91ae-364da2661108 www.vupen.com Broken Link
[SECURITY] Fedora 13 Update: udunits2-2.1.19-1.fc13 af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Third Party Advisory
oss-security - Re: Re: expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
oss-security - Regarding expat bug 1990430 af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List
[SECURITY] Fedora 13 Update: libtlen-0-0.10.20060309.fc13 af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Mailing List, Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Repository / Oval Repository af854a3a-2127-422b-91ae-364da2661108 oval.cisecurity.org Mailing List, Third Party Advisory
Pony Mail! af854a3a-2127-422b-91ae-364da2661108 lists.apache.org Third Party Advisory
Fedora update for PyXML - Secunia.com af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
USN-890-1: Expat vulnerabilities | Ubuntu af854a3a-2127-422b-91ae-364da2661108 www.ubuntu.com Third Party Advisory
Security Alerts - Secunia af854a3a-2127-422b-91ae-364da2661108 secunia.com Broken Link
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
Pony Mail! MITRE lists.apache.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

OrganizationPublishedContributorStatement
Red Hat2010-03-05Tomas HogerRed Hat is aware of this issue and is tracking it via the following bug: https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2009-3720 The Red Hat Security Response Team has rated this issue as having moderate security impact in Python, a future update may address this flaw. If a system has PyXML installed, Python will use PyXML for expat-related functions and is then not vulnerable to the issue.

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report