Critical Memory Overflow Vulnerability in Python AIOHTTP Package
Summary
DEBIAN-CVE-2026-54277: 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 connections simultaneously. The package is widely used for its efficiency and ease of use, but it has a critical vulnerability that can lead to denial of service (DoS) attacks if not addressed.
Vulnerability Detail
Prior to version 3.14.1, AIOHTTP's C parser had a flaw that allowed attackers to bypass the max_line_size check in HTTP requests. This could enable an attacker to send oversized lines, consuming excessive memory and potentially crashing the server. This vulnerability poses a significant risk, especially for applications relying on the C parser for performance.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
If immediate updating is not possible, consider switching to the pure Python parser by modifying your application code to use the 'aiohttp.web' module instead of the C parser. This can be done by setting the 'parser' parameter to 'aiohttp.web.Request' in your application configuration.
Conclusion
The vulnerability in the AIOHTTP package poses a serious risk to applications using the C parser, allowing for potential denial of service attacks. It is crucial to update to version 3.14.1 or later to mitigate this risk. For those unable to update immediately, switching to the pure Python parser can serve as a temporary solution.
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FAQ
The vulnerability allows attackers to bypass memory limits in the AIOHTTP C parser, leading to potential denial of service.
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The primary risk is denial of service (DoS), where an attacker can crash your server by consuming excessive memory.
Yes, the vulnerability is fixed in version 3.14.1 of the python-aiohttp package.
Consider using the pure Python parser as a temporary workaround until you can update to the patched version.
References
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