PYSEC-2026-1106

vendorUSosv

AIOHTTP vulnerable to DoS through chunked messages

view advisory published 2026-07-07Licence: CC-BY-4.0

### Summary Handling of chunked messages can result in excessive blocking CPU usage when receiving a large number of chunks. ### Impact If an application makes use of the `request.read()` method in an endpoint, it may be possible for an attacker to cause the server to spend a moderate amount of blocking CPU time (e.g. 1 second) while processing the request. This could potentially lead to DoS as the server would be unable to handle other requests during that time. ----- Patch: https://github.com/aio-libs/aiohttp/commit/dc3170b56904bdf814228fae70a5501a42a6c712 Patch: https://github.com/aio-libs/aiohttp/commit/4ed97a4e46eaf61bd0f05063245f613469700229

01

describes (1)

Related CVEs.

IDseverity exploitable
CVE-2025-69229USmedium5.3—
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. In versions 3.13.2 and below, handling of chunked messages can result in excessive blocking CPU usag…
02

references

External citations — patches, advisories, analysis.

scry

Advisories like this name the exposed products attackers go after on your perimeter. See what is exposed on your perimeter with a free passive scan.

Free scan