Answer in brief
CVE-2026-128131 records a High severity (CVSS 8.7) vulnerability in AIOHTTP: Concatenated compressed streams cause excessive CPU use. The current sources do not mark it as known exploited. The current feed maps aio-libs/aiohttp (generic). 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). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| aio-libs/aiohttpgeneric | <3.14.4 | 3.14.4 |
Published upstream
Nov 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 13, 2026
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, aiohttp decompresses each member of a payload containing many concatenated gzip, deflate, or zstd streams by passing the entire remaining input to a new decompressor, causing quadratic CPU use. Empty members produce no output, so client_max_size and output backpressure do not limit the work. A remote attacker can block a server event loop with a crafted compressed request body or WebSocket message, and a malicious server can similarly block a client. This issue is fixed in version 3.14.4.
Quoted source text, attributed separately from HOL analysis.