Security Update for Python 3.11: Mitigating Denial of Service Vulnerabilities
Summary
ALSA-2026:1410: Moderate: python3.11 security update. Affects python3.11 versions < 3.11.13-5.el9_7. Fixed in 3.11.13-5.el9_7. How to fix ↓
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Background
Python 3.11 is an advanced, interpreted programming language known for its object-oriented features, dynamic typing, and extensive libraries. It is widely used for web development, data analysis, artificial intelligence, and more. However, recent vulnerabilities have been identified that could lead to denial of service attacks, affecting the stability and security of applications built on this version.
Vulnerability Detail
The vulnerabilities in Python 3.11 stem from two main issues: excessive read buffering in the http.client module (CVE-2025-13836) and a quadratic algorithm in the xml.dom.minidom module that can lead to denial of service (CVE-2025-12084). These vulnerabilities can be exploited by attackers to cause applications to become unresponsive, potentially leading to service outages and impacting user experience.
How To Fix
Minimum fixed version
3.11.13-5.el9_7
This is the first release that contains the fix.
sudo dnf update python3.11Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, consider implementing rate limiting on the affected modules to mitigate the impact of potential denial of service attacks until the update can be applied.
Conclusion
In summary, Python 3.11 has critical vulnerabilities that can lead to denial of service attacks. It is crucial to update to the latest patched version to ensure the security and stability of applications. Utilizing tools like Vulert can help monitor and alert for such vulnerabilities in real-time.
See every vulnerability recorded for python3.11 →
FAQ
The main vulnerabilities include excessive read buffering in http.client and a quadratic algorithm in xml.dom.minidom, both of which can lead to denial of service.
You can use Vulert's playground at Vulert Scanner to check if your application is affected by these vulnerabilities without needing to sign up.
Exploitation of these vulnerabilities can lead to denial of service, causing applications to become unresponsive and affecting user experience.
Yes, a patch is available in version 3.11.13-5.el9_7 of Python 3.11. It is recommended to update to this version.
If immediate updating is not possible, consider implementing rate limiting on the affected modules as a temporary workaround.
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