CVE-2009-3720
MEDIUM · CVSS 5.0EPSS 27.9%EU EUVD
The 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.
Key facts
- CVSS score
- 5.0 (v2.0)
- Severity
- MEDIUM
- CVSS vector
AV:N/AC:L/Au:N/C:N/I:N/A:P- EPSS score
- 27.9% (98th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2009-3693)
- Published
- November 3, 2009
- NVD last modified
- July 20, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2009-3693 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.
View on the EU Vulnerability DatabaseAffected products
- apache / http server
- libexpat project / libexpat
- python / python
- python / pyxml
References
- http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmltok_impl.c?r1=1.13&r2=1.15&view=patch(Exploit)
- http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmltok_impl.c?view=log(Mailing List, Third Party Advisory)
- http://lists.fedoraproject.org/pipermail/package-announce/2010-November/051228.html(Third Party Advisory)
- http://lists.fedoraproject.org/pipermail/package-announce/2010-November/051247.html(Mailing List, Third Party Advisory)
- http://lists.fedoraproject.org/pipermail/package-announce/2010-November/051367.html(Third Party Advisory)
- http://lists.fedoraproject.org/pipermail/package-announce/2010-November/051405.html(Third Party Advisory)
- http://lists.fedoraproject.org/pipermail/package-announce/2010-November/051442.html(Third Party Advisory)
- http://lists.opensuse.org/opensuse-security-announce/2009-11/msg00004.html(Third Party Advisory)
- http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00001.html(Third Party Advisory, VDB Entry)
- http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00002.html(Third Party Advisory, VDB Entry)
- http://lists.opensuse.org/opensuse-security-announce/2010-06/msg00001.html(Third Party Advisory, VDB Entry)
- http://lists.opensuse.org/opensuse-security-announce/2010-08/msg00001.html(Third Party Advisory, VDB Entry)
- http://lists.vmware.com/pipermail/security-announce/2010/000082.html(Broken Link)
- http://mail.python.org/pipermail/expat-bugs/2009-January/002781.html(Third Party Advisory)
- http://marc.info/?l=bugtraq&m=130168502603566&w=2(Mailing List, Third Party Advisory)
- http://secunia.com/advisories/37324(Broken Link)
- http://secunia.com/advisories/37537(Broken Link)
- http://secunia.com/advisories/37925(Broken Link)
- http://secunia.com/advisories/38050(Broken Link)
- http://secunia.com/advisories/38231(Broken Link)
- http://secunia.com/advisories/38794(Broken Link)
- http://secunia.com/advisories/38832(Broken Link)
- http://secunia.com/advisories/38834(Broken Link)
- http://secunia.com/advisories/39478(Broken Link)
- http://secunia.com/advisories/41701(Broken Link)
- http://secunia.com/advisories/42326(Broken Link)
- http://secunia.com/advisories/42338(Broken Link)
- http://secunia.com/advisories/43300(Broken Link)
- http://slackware.com/security/viewer.php?l=slackware-security&y=2011&m=slackware-security.486026(Mailing List, Third Party Advisory)
- http://sourceforge.net/tracker/index.php?func=detail&aid=1990430&group_id=10127&atid=110127(Mailing List, Third Party Advisory)
- http://sunsolve.sun.com/search/document.do?assetkey=1-66-273630-1(Broken Link)
- http://svn.python.org/view?view=rev&revision=74429(Permissions Required, Third Party Advisory)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:211(Permissions Required, Third Party Advisory)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:212(Broken Link)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:215(Broken Link)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:216(Broken Link)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:217(Broken Link)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:218(Broken Link)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:219(Broken Link)
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:220(Broken Link)
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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