Bug 2569890 (CVE-2026-123817)

Summary:	CVE-2026-123817 aiohttp: aiohttp: Denial of Service via memory exhaustion during WebSocket frame reassembly
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	Keywords:	Security
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Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in aiohttp. When reassembling incomplete WebSocket frames, the reader allocates separate memory objects for each incoming data fragment without enforcing an upper limit on the object count. A remote attacker, acting as a malicious client or server, can exploit this vulnerability by transmitting a frame split into numerous tiny segments. This behavior generates excessive memory overhead that bypasses configured message size thresholds, leading to a Denial of Service (DoS) from resource exhaustion.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-10 19:22:17 UTC

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.