Answer in brief
CVE-2026-123817 records a High severity (CVSS 8.7) vulnerability in AIOHTTP WebSocket frame reassembly permits excessive memory consumption from tiny reads. The current sources do not mark it as known exploited. The current feed maps aio-libs/aiohttp (generic), aiohttp (pip), aiohttp (pypi). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps aio-libs/aiohttp (generic), aiohttp (pip), aiohttp (pypi). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| aio-libs/aiohttpgeneric | <3.14.4 | 3.14.4 |
| aiohttppip | <=3.14.3 | 3.14.4 |
| aiohttppypi | >=0 <3.14.4 | 3.14.4 |
Published upstream
Nov 9, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 9, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 19, 2026
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.
Quoted source text, attributed separately from HOL analysis.