Critical Security Vulnerability in Python 3.14: Multiple Exploitable Flaws
Summary
RLSA-2026:19176: Important: python3.14 security update. Affects python3.14 versions < 0:3.14.4-2.el9_8. Fixed in 0:3.14.4-2.el9_8. How to fix ↓
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Background
Python 3.14 is an interpreted, interactive, object-oriented programming language widely used for various applications, including web development, data analysis, artificial intelligence, and more. It features modules, classes, exceptions, and high-level dynamic data types, making it versatile and powerful. However, recent vulnerabilities have been identified that could compromise the security of applications using this version.
Vulnerability Detail
The vulnerabilities in Python 3.14 include header newline injection, logging bypass in legacy .pyc file handling, incomplete control character validation in HTTP cookies, stack overflow issues with deeply nested DTD content models, command-line option injection via crafted URLs, HTTP header injection through CR/LF in proxy tunnel headers, arbitrary code execution or information disclosure via use-after-free in decompression modules, and remote debugging vulnerabilities leading to information disclosure and arbitrary code execution. These vulnerabilities can lead to severe security risks, including unauthorized access, data leakage, and system compromise.
How To Fix
Minimum fixed version
0:3.14.4-2.el9_8
This is the first release that contains the fix.
sudo dnf update python3.14Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary measure, avoid using the affected functionalities until the package is updated. For instance, refrain from using the webbrowser.open() API with untrusted URLs to prevent command injection.
Conclusion
The vulnerabilities identified in Python 3.14 pose significant risks to applications utilizing this version. It is crucial to update to the patched version 3.14.4-2.el9_8 to mitigate these risks. Users are encouraged to monitor their applications for vulnerabilities using tools like Vulert.
See every vulnerability recorded for python3.14 →
FAQ
The CVSS score of this vulnerability is 8.1, indicating a high severity level.
You can use Vulert's playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
The vulnerabilities can lead to unauthorized access, data leakage, arbitrary code execution, and system compromise, posing significant risks to applications.
Yes, Vulert can monitor and alert you in real-time for open-source vulnerabilities using just a manifest file like package-lock.json.
If immediate updates are not possible, avoid using the affected functionalities and monitor for any security advisories related to Python 3.14.
References
Related vulnerabilities
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