CVE-2026-69243

AIOHTTP: HTTP request smuggling via WebSocket upgrade

State
Published
Severity
6.3 Medium
Published
Aug 3, 2026
Updated
Aug 5, 2026
Reserved
Aug 3, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
4.06.3 MediumCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NGitHub_M

Weaknesses

  • CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Affected Products

ProductVersions
aiohttpaio-libs
  • < 3.14.2Affected

References

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