AIOHTTP: HTTP request smuggling via WebSocket upgrade
33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 6.3epss 0.3%
from disclosure to weapon1 days
Published on NVDAug 3
1st PoC+1d
exploitation probability
0.3%top 80% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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 · aiohttppublic PoCs found — 1
githubgithub.com/JVBotelho/cve-2026-69243-poc-aiohttp-smuggling★ 1⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.