CVE-2026-123817

Description

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, the WebSocket reader retains one bytes object for each transport read while reassembling an incomplete frame. A malicious peer can split a frame into many tiny reads so per-object overhead substantially exceeds the payload bytes allowed by max_msg_size. The condition affects a server receiving frames from a malicious client and a client receiving frames from a malicious server, and can cause excessive memory consumption or denial of service. This issue is fixed in version 3.14.4.

References

• https://github.com/aio-libs/aiohttp/commit/09bcaa73ff084a0c539bbf16a0a78743acb7141f
• https://github.com/aio-libs/aiohttp/commit/6a4f6682817839313b04b8e5cea2b39c1a88ab4f
• https://github.com/aio-libs/aiohttp/pull/13352
• https://github.com/aio-libs/aiohttp/pull/13612
• https://github.com/aio-libs/aiohttp/releases/tag/v3.14.4