# CVE-2013-0340: Python 3.8 and 3 others: expat before version 2.4.0 does not properly handle entities expansion unless an application developer…

CVE-2013-0340 is fixed in 3 products on 2 platforms, first by Python 3.9 3.9.7, released August 30, 2021. 3 other affected products have no fix yet. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2013-0340
- Priority: Routine
- CVSS: 6.8 (Important)
- EPSS: 0.1943
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 21, 2014
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2013-0340

## Description

expat before version 2.4.0 does not properly handle entities expansion unless an application developer uses the XML_SetEntityDeclHandler function, which allows remote attackers to cause a denial of service (resource consumption), send HTTP requests to intranet servers, or read arbitrary files via a crafted XML document, aka an XML External Entity (XXE) issue.  NOTE: it could be argued that because expat already provides the ability to disable external entity expansion, the responsibility for resolving this issue lies with application developers; according to this argument, this entry should be REJECTed, and each affected application would need its own CVE.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Python 3.9 | 3.9.7 | [Python 3.9 3.9.7](https://patchblox.com/security/data/fix/windows-app/python.python.3.9-3.9.7.md) | Aug 30, 2021 |
| Linux | expat RHEL 8 | 0:2.5.0-1.el8_10 | [RHSA-2025:21776](https://patchblox.com/security/data/fix/linux/rhsa-2025-21776.md) | Nov 19, 2025 |
| Linux | expat RHEL 9 | 0:2.4.9-1.el9_1 | [RHBA-2022:8290](https://patchblox.com/security/data/fix/linux/rhba-2022-8290.md) | Nov 15, 2022 |
| Linux | expat almalinux 8 | 2.5.0-1.el8_10 | [ALSA-2025:21776](https://patchblox.com/security/data/fix/linux/alsa-2025-21776.md) | Nov 19, 2025 |
| Linux | expat-devel RHEL 8 | 0:2.5.0-1.el8_10 | [RHSA-2025:21776](https://patchblox.com/security/data/fix/linux/rhsa-2025-21776.md) | Nov 19, 2025 |
| Linux | expat-devel RHEL 9 | 0:2.4.9-1.el9_1 | [RHBA-2022:8290](https://patchblox.com/security/data/fix/linux/rhba-2022-8290.md) | Nov 15, 2022 |
| Linux | expat-devel almalinux 8 | 2.5.0-1.el8_10 | [ALSA-2025:21776](https://patchblox.com/security/data/fix/linux/alsa-2025-21776.md) | Nov 19, 2025 |

## No fix yet

| Platform | Product | Status |
|---|---|---|
| Windows apps | Python 3.6 | no-fix |
| Windows apps | Python 3.7 | no-fix |
| Windows apps | Python 3.8 | no-fix |

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Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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