CVE-2026-69243mediumCWE-444

CVE-2026-69243: medium-severity vulnerability in aio-libs aiohttp

AIOHTTP: HTTP request smuggling via WebSocket upgrade

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 6.3epss 0.4%
from disclosure to weapon1 day
Published on NVDAug 3
1st PoC+1d
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.2, the HTTP parsers were vulnerable to a request smuggling attack relating to WebSocket upgrades. If using the server-side component, an attacker may be able to execute a request smuggling vulnerability using an edge case in the WebSocket upgrade procedure. A WebSocket upgrade request with a body could cause the parser to switch protocols before the complete request body was received, leaving trailing bytes to be handled as upgraded-protocol or pipelined data rather than normal HTTP body data. This issue is fixed in version 3.14.2.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Affected products
aio-libs · aiohttp
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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