# CVE-2009-3720: expat: The updatePosition function in lib/xmltok_impl.c in libexpat in Expat2.0.1, as used in Python, PyXML, w3c-libwww, and...

CVE-2009-3720 is fixed in 7 products on 1 platform, first by expat 2.0.1-7ubuntu1, released December 4, 2009. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2009-3720
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.2792
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 3, 2009

## Description

The updatePosition function in lib/xmltok_impl.c in libexpat in Expat2.0.1, as used in Python, PyXML, w3c-libwww, and other software, allowscontext-dependent attackers to cause a denial of service (applicationcrash) via an XML document with crafted UTF-8 sequences that trigger abuffer over-read, a different vulnerability than CVE-2009-2625.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | expat Ubuntu 24.10 (oracular) | 2.0.1-7ubuntu1 | [expat 2.0.1-7ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-expat-2.0.1-7ubuntu1.md) | Dec 4, 2009 |
| Linux | expat Ubuntu 25.04 (plucky) | 2.0.1-7ubuntu1 | [expat 2.0.1-7ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-expat-2.0.1-7ubuntu1.md) | Dec 4, 2009 |
| Linux | libexpat1 Ubuntu 24.10 (oracular) | 2.0.1-7ubuntu1 | [libexpat1 2.0.1-7ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libexpat1-2.0.1-7ubuntu1.md) | Dec 4, 2009 |
| Linux | libexpat1 Ubuntu 25.04 (plucky) | 2.0.1-7ubuntu1 | [libexpat1 2.0.1-7ubuntu1](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libexpat1-2.0.1-7ubuntu1.md) | Dec 4, 2009 |
| Linux | libxmlrpc-c++8t64 Ubuntu 24.10 (oracular) | 1.06.27-1ubuntu7 | [libxmlrpc-c++8t64 1.06.27-1ubuntu7](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libxmlrpc-c-8t64-1.06.27-1ubuntu7.md) | Dec 4, 2009 |
| Linux | libxmlrpc-c++9 Ubuntu 25.04 (plucky) | 1.06.27-1ubuntu7 | [libxmlrpc-c++9 1.06.27-1ubuntu7](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libxmlrpc-c-9-1.06.27-1ubuntu7.md) | Dec 4, 2009 |
| Linux | libxmlrpc-core-c3t64 Ubuntu 24.10 (oracular) | 1.06.27-1ubuntu7 | [libxmlrpc-core-c3t64 1.06.27-1ubuntu7](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libxmlrpc-core-c3t64-1.06.27-1ubuntu7.md) | Dec 4, 2009 |
| Linux | libxmlrpc-core-c3t64 Ubuntu 25.04 (plucky) | 1.06.27-1ubuntu7 | [libxmlrpc-core-c3t64 1.06.27-1ubuntu7](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libxmlrpc-core-c3t64-1.06.27-1ubuntu7.md) | Dec 4, 2009 |
| Linux | libxmlrpc-util4 Ubuntu 25.04 (plucky) | 1.06.27-1ubuntu7 | [libxmlrpc-util4 1.06.27-1ubuntu7](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libxmlrpc-util4-1.06.27-1ubuntu7.md) | Dec 4, 2009 |
| Linux | xmlrpc-api-utils Ubuntu 24.10 (oracular) | 1.06.27-1ubuntu7 | [xmlrpc-api-utils 1.06.27-1ubuntu7](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-xmlrpc-api-utils-1.06.27-1ubuntu7.md) | Dec 4, 2009 |
| Linux | xmlrpc-api-utils Ubuntu 25.04 (plucky) | 1.06.27-1ubuntu7 | [xmlrpc-api-utils 1.06.27-1ubuntu7](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-xmlrpc-api-utils-1.06.27-1ubuntu7.md) | Dec 4, 2009 |

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