PyPI: python

CVE-2013-4238

Safety vulnerability ID: SFTY-20130818-11045

Safety legacy ID: pyup.io-45663

Python versions 2.6.9, 2.7.7, 3.2.6, 3.3.6 and 3.4.1 include a fix for CVE-2013-4238: The ssl.match_hostname function in the SSL module in Python 2.6 through 3.4 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408. https://bugs.python.org/issue18709

PythonPyPINVDNVD
Created at: Jul 5, 2026Updated at: Jul 5, 2026

Overview

Python versions 2.6.9, 2.7.7, 3.2.6, 3.3.6 and 3.4.1 include a fix for CVE-2013-4238: The ssl.match_hostname function in the SSL module in Python 2.6 through 3.4 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408. https://bugs.python.org/issue18709

Advisory

Python versions 2.6.9, 2.7.7, 3.2.6, 3.3.6 and 3.4.1 include a fix for CVE-2013-4238: The ssl.match_hostname function in the SSL module in Python 2.6 through 3.4 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408. https://bugs.python.org/issue18709

Affected Package

Affecting python package, versions<2.6.9>=2.7.0a0,<2.7.7>=3.2.0a0,<3.2.6>=3.3.0a0,<3.3.6>=3.4.0a0,<3.4.1

Also affects

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How to Fix

Upgradepythonto2.6.92.7.73.2.63.3.63.4.1or higher.

Mitigation and Workarounds

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Vulnerable Functions

Functions linked to known vulnerabilities.

Vulnerable function data is available for Enterprise customers

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References

Safety

Verified by Safety

Our Cybersecurity Intelligence Team reviewed this vulnerability. We combine public data with our own research to find issues not yet reported to public sources.

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