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PYSEC-2026-3546
AIOHTTP: HTTP request smuggling via WebSocket upgrade
Quick fix
PYSEC-2026-3546 — aiohttp: upgrade to the fixed version with the command below.
pip install --upgrade 'aiohttp>=3.14.2'Details
### Summary
The HTTP parsers were vulnerable to a request smuggling attack relating to WebSocket upgrades.
### Impact
If using the server-side component, it may be possible for an attacker to execute a request smuggling vulnerability using an edge case in the WebSocket upgrade procedure. AIOHTT is unaware of any public exploit code.
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Patch: https://github.com/aio-libs/aiohttp/commit/6ae358f0983c3f4d6f67692b2f8e65dc8e091c98
Are you affected?
Enter the version of the package you're using.
Affected packages
References
- https://github.com/aio-libs/aiohttp/security/advisories/GHSA-mfx4-hv73-q22v[WEB]
- https://github.com/aio-libs/aiohttp/pull/13017[WEB]
- https://github.com/aio-libs/aiohttp/commit/6ae358f0983c3f4d6f67692b2f8e65dc8e091c98[WEB]
- https://github.com/aio-libs/aiohttp[PACKAGE]
- https://github.com/aio-libs/aiohttp/releases/tag/v3.14.2[WEB]
- https://pypi.org/project/aiohttp[PACKAGE]
- https://github.com/advisories/GHSA-mfx4-hv73-q22v[ADVISORY]
- https://nvd.nist.gov/vuln/detail/CVE-2026-69243[ADVISORY]