CVE-2023-36632: High severity Python Python vulnerability

Published Jun 25, 2023
·
Updated

DISPUTED 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.

Other sources

Python is vulnerable to a denial of service, caused by a RecursionError in email.utils.parseaddr #103800. By sending a specially crafted argument, a remote attacker could exploit this vulnerability to cause a denial of service condition.

IBM

Affected Software

2 affected components
Python Python<=3.11.4
IBM QRadar Network Packet Capture<=7.5.0 - 7.5.0 Update Package 7

Event History

Jun 25, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Disputed
06:15 PM
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software
Jul 23, 2024
Data Sourced
via IBM·12:00 AM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2023-36632?

CVE-2023-36632 is a vulnerability in the legacy email.utils.parseaddr function in Python through 3.11.4 that allows attackers to trigger a "RecursionError: maximum recursion depth exceeded while calling a Python object" by providing a crafted argument.

2

What is the severity of CVE-2023-36632?

CVE-2023-36632 has a severity rating of 7.5 (high).

3

Which version of Python is affected by CVE-2023-36632?

Python versions up to and including 3.11.4 are affected by CVE-2023-36632.

4

How can attackers exploit CVE-2023-36632?

Attackers can exploit CVE-2023-36632 by providing a crafted argument to the email.utils.parseaddr function.

5

Are there any public references for CVE-2023-36632?

Yes, you can find more information about CVE-2023-36632 in the Python documentation (https://docs.python.org/3/library/email.html, https://docs.python.org/3/library/email.utils.html) and a PoC on GitHub (https://github.com/Daybreak2019/PoC_python3.9_Vul/blob/main/RecursionError-email.utils.parseaddr.py).

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