# CVE-2017-9233: Python 3.5 and 1 other: XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers…

CVE-2017-9233 is fixed in 2 products on 1 platform, first by Python 3.6 3.6.2, released July 17, 2017. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2017-9233
- Priority: High
- CVSS: 7.5
- EPSS: 0.0874
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 25, 2017
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2017-9233

## Description

XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers to put the parser in an infinite loop using a malformed external entity definition from an external DTD.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Python 3.5 | 3.5.4 | [Python 3.5 3.5.4](https://patchblox.com/security/data/fix/windows-app/python.python.3.5-3.5.4.md) | Aug 7, 2017 |
| Windows apps | Python 3.6 | 3.6.2 | [Python 3.6 3.6.2](https://patchblox.com/security/data/fix/windows-app/python.python.3.6-3.6.2.md) | Jul 17, 2017 |

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Data as of 2026-11-07T06:34:28Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo