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TI-2009-03544 Aliases CVE-2009-3720GHSA-pj3x-74qr-vrr4

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

Priority MEDIUM 45Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
— Not recorded in CVSS 2.0
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · Partial
Fix status
Fixed

Attack profile from CVSS 2.0 · NVD. Fix status from CNA and Red Hat.

Summary

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.

Why it matters now

EPSS 0.27924 98th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed Red Hat: 7 advisories

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:libexpat_project:libexpat:2.0.1:*:*:*:*:*:*:*2.0.1Vulnerablelibexpat project
cpe:2.3:a:python:python:*:*:*:*:*:*:*:*all versionsRunning onpython-pillow
cpe:2.3:a:python:pyxml:*:*:*:*:*:*:*:*all versionsRunning onpython-pillow
cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*2.0.35 to before 2.0.64; 2.2.0 to before 2.2.17VulnerableApache
  • cpe:2.3:a:libexpat_project:libexpat:2.0.1:*:*:*:*:*:*:* Versions 2.0.1 Vulnerable ·libexpat project
  • cpe:2.3:a:python:python:*:*:*:*:*:*:*:* Versions all versions Running on ·python-pillow
  • cpe:2.3:a:python:pyxml:*:*:*:*:*:*:*:* Versions all versions Running on ·python-pillow
  • cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* Versions 2.0.35 to before 2.0.64; 2.2.0 to before 2.2.17 Vulnerable ·Apache

Remediation

Red Hat 7 advisories

  • RHSA-2017:3239 Released 2017-11-16 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 6.4.18 security update
    • Red Hat JBoss Enterprise Application Platform 6.4
  • RHSA-2011:0896 Released 2011-06-22 · Red Hat rating Moderate
    JBoss Enterprise Web Server 1.0.2 update
    • Red Hat JBoss Web Server 1.0
  • RHSA-2011:0491 Released 2011-05-05 · Red Hat rating Moderate
    python security update
    • Red Hat Enterprise Linux AS version 4 python-2.3.4-14.10.el4, python-2.3.4-14.10.el4.i386, python-2.3.4-14.10.el4.ia64 +17
    • Red Hat Enterprise Linux Desktop version 4 python-2.3.4-14.10.el4, python-2.3.4-14.10.el4.i386, python-devel-2.3.4-14.10.el4 +7
    • Red Hat Enterprise Linux ES version 4 python-2.3.4-14.10.el4, python-2.3.4-14.10.el4.i386, python-2.3.4-14.10.el4.ia64 +12
    • Red Hat Enterprise Linux WS version 4 python-2.3.4-14.10.el4, python-2.3.4-14.10.el4.i386, python-2.3.4-14.10.el4.ia64 +12
Show 4 more Red Hat advisories
  • RHSA-2011:0492 Released 2011-05-05 · Red Hat rating Moderate
    python security update
    • Red Hat Enterprise Linux (v. 5 server) python-2.4.3-44.el5, python-2.4.3-44.el5.i386, python-2.4.3-44.el5.ia64 +17
    • Red Hat Enterprise Linux Desktop (v. 5 client) python-2.4.3-44.el5, python-2.4.3-44.el5.i386, python-libs-2.4.3-44.el5 +5
    • Red Hat Enterprise Linux Desktop Workstation (v. 5 client) python-2.4.3-44.el5, python-devel-2.4.3-44.el5, python-devel-2.4.3-44.el5.i386
  • RHSA-2010:0002 Released 2010-01-04 · Red Hat rating Moderate
    PyXML security update
    • Red Hat Enterprise Linux (v. 5 server) PyXML-0.8.4-4.el5_4.2, PyXML-0.8.4-4.el5_4.2.i386, PyXML-0.8.4-4.el5_4.2.ia64 +1
    • Red Hat Enterprise Linux AS version 4 PyXML-0.8.3-6.el4_8.2, PyXML-0.8.3-6.el4_8.2.i386, PyXML-0.8.3-6.el4_8.2.ia64 +1
    • Red Hat Enterprise Linux Desktop (v. 5 client) PyXML-0.8.4-4.el5_4.2, PyXML-0.8.4-4.el5_4.2.i386
    • Red Hat Enterprise Linux Desktop version 4 PyXML-0.8.3-6.el4_8.2, PyXML-0.8.3-6.el4_8.2.i386
    • Red Hat Enterprise Linux ES version 4 PyXML-0.8.3-6.el4_8.2, PyXML-0.8.3-6.el4_8.2.i386, PyXML-0.8.3-6.el4_8.2.ia64
    • Red Hat Enterprise Linux WS version 4 PyXML-0.8.3-6.el4_8.2, PyXML-0.8.3-6.el4_8.2.i386, PyXML-0.8.3-6.el4_8.2.ia64
  • RHSA-2009:1625 Released 2009-12-07 · Red Hat rating Moderate
    expat security update
    • Red Hat Desktop version 3 expat-1.95.5-6.2, expat-1.95.5-6.2.i386, expat-devel-1.95.5-6.2 +1
    • Red Hat Enterprise Linux (v. 5 server) expat-1.95.8-8.3.el5_4.2, expat-1.95.8-8.3.el5_4.2.i386, expat-1.95.8-8.3.el5_4.2.ia64 +5
    • Red Hat Enterprise Linux AS version 3 expat-1.95.5-6.2, expat-1.95.5-6.2.i386, expat-1.95.5-6.2.ia64 +5
    • Red Hat Enterprise Linux AS version 4 expat-1.95.7-4.el4_8.2, expat-1.95.7-4.el4_8.2.i386, expat-1.95.7-4.el4_8.2.ia64 +5
    • Red Hat Enterprise Linux Desktop (v. 5 client) expat-1.95.8-8.3.el5_4.2, expat-1.95.8-8.3.el5_4.2.i386
    • Red Hat Enterprise Linux Desktop Workstation (v. 5 client) expat-1.95.8-8.3.el5_4.2, expat-devel-1.95.8-8.3.el5_4.2, expat-devel-1.95.8-8.3.el5_4.2.i386
    • Red Hat Enterprise Linux Desktop version 4 expat-1.95.7-4.el4_8.2, expat-1.95.7-4.el4_8.2.i386, expat-devel-1.95.7-4.el4_8.2 +1
    • Red Hat Enterprise Linux ES version 3 expat-1.95.5-6.2, expat-1.95.5-6.2.i386, expat-1.95.5-6.2.ia64 +3
    • Red Hat Enterprise Linux ES version 4 expat-1.95.7-4.el4_8.2, expat-1.95.7-4.el4_8.2.i386, expat-1.95.7-4.el4_8.2.ia64 +3
    • Red Hat Enterprise Linux WS version 3 expat-1.95.5-6.2, expat-1.95.5-6.2.i386, expat-1.95.5-6.2.ia64 +3
    • Red Hat Enterprise Linux WS version 4 expat-1.95.7-4.el4_8.2, expat-1.95.7-4.el4_8.2.i386, expat-1.95.7-4.el4_8.2.ia64 +3
  • RHSA-2009:1572 Released 2009-11-10 · Red Hat rating Moderate
    4Suite security update
    • Red Hat Desktop version 3 4Suite-0.11.1-15, 4Suite-0.11.1-15.i386
    • Red Hat Enterprise Linux AS version 3 4Suite-0.11.1-15, 4Suite-0.11.1-15.i386, 4Suite-0.11.1-15.ia64 +1
    • Red Hat Enterprise Linux AS version 4 4Suite-1.0-3.el4_8.1, 4Suite-1.0-3.el4_8.1.i386, 4Suite-1.0-3.el4_8.1.ia64 +1
    • Red Hat Enterprise Linux Desktop version 4 4Suite-1.0-3.el4_8.1, 4Suite-1.0-3.el4_8.1.i386
    • Red Hat Enterprise Linux ES version 3 4Suite-0.11.1-15, 4Suite-0.11.1-15.i386, 4Suite-0.11.1-15.ia64
    • Red Hat Enterprise Linux ES version 4 4Suite-1.0-3.el4_8.1, 4Suite-1.0-3.el4_8.1.i386, 4Suite-1.0-3.el4_8.1.ia64
    • Red Hat Enterprise Linux WS version 3 4Suite-0.11.1-15, 4Suite-0.11.1-15.i386, 4Suite-0.11.1-15.ia64
    • Red Hat Enterprise Linux WS version 4 4Suite-1.0-3.el4_8.1, 4Suite-1.0-3.el4_8.1.i386, 4Suite-1.0-3.el4_8.1.ia64

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Desktop version 3Fixed RHSA-2009:1572, RHSA-2009:1625
Red Hat Enterprise Linux (v. 5 server)Fixed RHSA-2009:1625, RHSA-2010:0002, RHSA-2011:0492
Red Hat Enterprise Linux AS version 3Fixed RHSA-2009:1572, RHSA-2009:1625
Red Hat Enterprise Linux AS version 4Fixed RHSA-2009:1572, RHSA-2009:1625, RHSA-2010:0002, RHSA-2011:0491
Red Hat Enterprise Linux Desktop (v. 5 client)Fixed RHSA-2009:1625, RHSA-2010:0002, RHSA-2011:0492
Red Hat Enterprise Linux Desktop Workstation (v. 5 client)Fixed RHSA-2009:1625, RHSA-2011:0492
Red Hat Enterprise Linux Desktop version 4Fixed RHSA-2009:1572, RHSA-2009:1625, RHSA-2010:0002, RHSA-2011:0491
Red Hat Enterprise Linux ES version 3Fixed RHSA-2009:1572, RHSA-2009:1625
Red Hat Enterprise Linux ES version 4Fixed RHSA-2009:1572, RHSA-2009:1625, RHSA-2010:0002, RHSA-2011:0491
Red Hat Enterprise Linux WS version 3Fixed RHSA-2009:1572, RHSA-2009:1625
Red Hat Enterprise Linux WS version 4Fixed RHSA-2009:1572, RHSA-2009:1625, RHSA-2010:0002, RHSA-2011:0491
Red Hat JBoss Enterprise Application Platform 6.4Fixed RHSA-2017:3239
Red Hat JBoss Web Server 1.0Fixed RHSA-2011:0896
Not affected: 3 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2009-3720
  2. 2026-10-03 Alias added: GHSA-pj3x-74qr-vrr4

References

Exploit 1

Advisory 56

Other 22

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences