# CVE-2023-36632: Python 3.10 and 8 others: The legacy email.utils.parseaddr function in Python through 3.11.4 allows attackers to trigger "RecursionError:…

CVE-2023-36632 is fixed in Python 3.11 on 1 platform by Python 3.11 3.11.5 (version 3.11.5), released August 24, 2023. 7 other affected products have no fix yet. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2023-36632
- Priority: High
- CVSS: 7.5
- EPSS: 0.0158
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 25, 2023
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2023-36632

## Description

The legacy email.utils.parseaddr function in Python through 3.11.4 allows attackers to trigger "RecursionError: maximum recursion depth exceeded while calling a Python object" via a crafted argument. This argument is plausibly an untrusted value from an application's input data that was supposed to contain a name and an e-mail address. NOTE: email.utils.parseaddr is categorized as a Legacy API in the documentation of the Python email package. Applications should instead use the email.parser.BytesParser or email.parser.Parser class. NOTE: the vendor's perspective is that this is neither a vulnerability nor a bug. The email package is intended to have size limits and to throw an exception when limits are exceeded; they were exceeded by the example demonstration code.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Python 3.11 | 3.11.5 | [Python 3.11 3.11.5](https://patchblox.com/security/data/fix/windows-app/python.python.3.11-3.11.5.md) | Aug 24, 2023 |

## No fix yet

| Platform | Product | Status |
|---|---|---|
| Windows apps | Python 2 | no-fix |
| Windows apps | Python 3.10 | no-fix |
| Windows apps | Python 3.5 | no-fix |
| Windows apps | Python 3.6 | no-fix |
| Windows apps | Python 3.7 | no-fix |
| Windows apps | Python 3.8 | no-fix |
| Windows apps | Python 3.9 | no-fix |

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Data as of 2026-11-08T00:53:09Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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