Memory Exhaustion Vulnerability in Python AIOHTTP Package
Summary
DEBIAN-CVE-2026-34513: AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Affects python-aiohttp versions 3.10.0-1 – 3.9.5-1. No fix is published. How to fix ↓
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Background
AIOHTTP is an asynchronous HTTP client/server framework designed for Python's asyncio library. It allows developers to build web applications and services that can handle multiple requests concurrently, making it a popular choice for modern web development. The package is widely used due to its efficiency and ease of use, but it has recently been identified as having a significant vulnerability that could lead to excessive memory usage.
Vulnerability Detail
The vulnerability, identified as CVE-2026-34513, is rooted in an unbounded DNS cache within the AIOHTTP framework. This flaw can lead to excessive memory consumption, potentially resulting in a Denial of Service (DoS) situation where the application becomes unresponsive due to resource exhaustion. The issue affects all versions of the package prior to 3.13.4, making it critical for users to address it promptly.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
As a temporary workaround, users can limit the size of the DNS cache manually in their application settings to mitigate memory usage until they can upgrade to the patched version. This can be done by configuring the DNS resolver settings in the AIOHTTP application.
Conclusion
The AIOHTTP package has a critical vulnerability (CVE-2026-34513) that can lead to excessive memory usage and potential Denial of Service. Users are strongly advised to update to version 3.13.4 or later to mitigate this risk. Temporary workarounds are available, but upgrading is the most effective solution.
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FAQ
CVE-2026-34513 is a vulnerability in the AIOHTTP package that can lead to excessive memory usage due to an unbounded DNS cache.
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The primary impact is a Denial of Service (DoS) situation, where the application may become unresponsive due to excessive memory consumption.
You can update the AIOHTTP package by running the command 'pip install --upgrade aiohttp' in your terminal.
Yes, you can limit the size of the DNS cache in your application settings as a temporary workaround until you can upgrade.
References
Related vulnerabilities
Recent vulnerabilities recorded for python-aiohttp.
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