What’s Vulnerable › Vulnerabilities

CVE-2009-3560

• Severity: medium (CVSS 5.0 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 24.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2009-12-04 · updated 2026-06-16
• Weakness: CWE-119

Description

The big2_toUtf8 function in lib/xmltok.c in libexpat in Expat 2.0.1, as used in the XML-Twig module for Perl, allows context-dependent attackers to cause a denial of service (application crash) via an XML document with malformed UTF-8 sequences that trigger a buffer over-read, related to the doProlog function in lib/xmlparse.c, a different vulnerability than CVE-2009-2625 and CVE-2009-3720.

Affected products

• Apache HTTP Server: from 2.0.35 before 2.0.64; from 2.2.0 before 2.2.17 — fixed in 2.0.64, 2.2.17
• libexpat project libexpat: 2.0.1

How to fix

Upgrade to a fixed version: Apache HTTP Server 2.0.64, 2.2.17. Check the vendor advisory for mitigations.

References

• http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmlparse.c?r1=1.164&r2=1.165
• http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmlparse.c?view=log#rev1.165
• http://lists.opensuse.org/opensuse-security-announce/2010-01/msg00007.html
• http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00001.html
• http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00002.html
• http://lists.opensuse.org/opensuse-security-announce/2010-06/msg00001.html
• http://lists.opensuse.org/opensuse-security-announce/2010-08/msg00001.html
• http://lists.vmware.com/pipermail/security-announce/2010/000082.html
• http://mail.python.org/pipermail/expat-bugs/2009-November/002846.html
• http://marc.info/?l=bugtraq&m=130168502603566&w=2
• http://secunia.com/advisories/37537
• http://secunia.com/advisories/38231

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