CVE-2009-3720 - CVE House
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Status published Medium CVE-2009-3720

The updatePosition function in lib/xmltok_impl.c in libexpat in Expat 2.0.1,...

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

libexpat project

View all reports →

Affected Software

libexpat, http server
Vulnerable Versions:
2.0.1, 2.0.35, 2.2.0

Timeline

Official Publish: November 3rd, 2009
Last Modified: August 7th, 2024
Added to House: July 19th, 2026

CVSS Vectors

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.