CVE-2023-36632 : Vulnerability Insights and Analysis

This article provides insights into CVE-2023-36632, a vulnerability in Python that allows attackers to trigger a recursion error via a crafted argument.

Understanding CVE-2023-36632

CVE-2023-36632 is a vulnerability in the legacy email.utils.parseaddr function in Python through version 3.11.4. Attackers can exploit this vulnerability to trigger a 'RecursionError: maximum recursion depth exceeded while calling a Python object' by providing a specially crafted argument.

What is CVE-2023-36632?

The vulnerability in the email.utils.parseaddr function allows attackers to cause a recursion error by passing a malicious argument. This argument is likely to be an untrusted value from an application's input data that was expected to include a name and an e-mail address.

The Impact of CVE-2023-36632

This vulnerability can be exploited by attackers to cause a denial of service (DoS) condition on systems running the affected Python versions. By triggering the recursion error, an attacker could potentially disrupt the normal operation of an application.

Technical Details of CVE-2023-36632

The following section outlines the technical aspects of CVE-2023-36632, including its vulnerability description, affected systems and versions, and exploitation mechanism.

Vulnerability Description

The vulnerability arises from the email.utils.parseaddr function in Python, which fails to handle certain inputs correctly, leading to a recursion error when a crafted argument is provided.

Affected Systems and Versions

Python versions up to 3.11.4 are impacted by this vulnerability. Any system using the legacy email.utils.parseaddr function is susceptible to exploitation.

Exploitation Mechanism

Attackers can exploit CVE-2023-36632 by providing a specially crafted argument to the email.utils.parseaddr function. This argument triggers a recursion error, causing a DoS condition.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-36632, it is recommended to take immediate steps and implement long-term security practices to ensure system resilience.

Immediate Steps to Take

Update Python to a non-affected version or apply patches provided by the vendor.
Avoid passing untrusted input to the email.utils.parseaddr function.

Long-Term Security Practices

Review and update Python code to replace the use of email.utils.parseaddr with email.parser.BytesParser or email.parser.Parser.
Regularly monitor for security updates and apply patches promptly to prevent exploitation.

Patching and Updates

Vendor patches and updates for Python can help address the vulnerability in email.utils.parseaddr and strengthen the overall security posture of the system.