medium
5
CWE
Advisory Published
CVE Published
Updated

CVE-2009-3720

First published: Sat Jan 17 2009(Updated: )

Peter Valchev discovered a flaw in the way expat handled malformed UTF-8 sequences when processing XML files. Incorrect UTF-8 sequenced could cause expat to fail to properly detect end of input and continue reading behind the end of input buffer. This results in a crash once reading reaches unmapped memory. Non-public upstream bug report: <a href="http://sourceforge.net/tracker/?func=detail&amp;aid=1990430&amp;group_id=10127&amp;atid=110127">http://sourceforge.net/tracker/?func=detail&amp;aid=1990430&amp;group_id=10127&amp;atid=110127</a> Contents of the report leaked via expat-bugs mailing list posts: <a href="http://mail.python.org/pipermail/expat-bugs/2009-January/002781.html">http://mail.python.org/pipermail/expat-bugs/2009-January/002781.html</a> Upstream patch: <a href="http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmltok_impl.c?r1=1.13&amp;r2=1.15">http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmltok_impl.c?r1=1.13&amp;r2=1.15</a> References: <a href="http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=551936">http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=551936</a> <a href="https://bugs.gentoo.org/show_bug.cgi?id=280615">https://bugs.gentoo.org/show_bug.cgi?id=280615</a>

Credit: secalert@redhat.com

Affected SoftwareAffected VersionHow to fix
redhat/expat<0:1.95.7-4.el4_8.2
0:1.95.7-4.el4_8.2
redhat/python<0:2.3.4-14.10.el4
0:2.3.4-14.10.el4
redhat/expat<0:1.95.8-8.3.el5_4.2
0:1.95.8-8.3.el5_4.2
redhat/python<0:2.4.3-44.el5
0:2.4.3-44.el5
redhat/expat<2.1.0
2.1.0
IBM Engineering Requirements Management DOORS Web Access<=9.7.2.8
IBM Rational DOORS Web Access<=9.7.2.8
IBM Rational DOORS<=9.6.1.x
All of
Libexpat=2.0.1
Any of
PyXML
Python 2.7
Apache HTTP Server>=2.0.35<2.0.64
Apache HTTP Server>=2.2.0<2.2.17
Expat=2.0.1
PyXML
Python 2.7

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Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2009-3720?

    CVE-2009-3720 is considered a critical vulnerability due to its potential to cause application crashes.

  • How do I fix CVE-2009-3720?

    To mitigate CVE-2009-3720, update the affected expat or python packages to the specified remedial versions in the advisory.

  • Which software products are affected by CVE-2009-3720?

    CVE-2009-3720 affects expat, python, and products such as IBM Engineering Requirements Management DOORS, along with Apache HTTP Server in specific versions.

  • What can happen if I don't address CVE-2009-3720?

    Neglecting to address CVE-2009-3720 can lead to application instability and security risks due to crashes when processing malformed XML.

  • Who discovered the CVE-2009-3720 vulnerability?

    CVE-2009-3720 was discovered by Peter Valchev.

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