CVE-2026-59881
AIOHTTP: WebSocket client accepts compressed frames without negotiated permessage-deflate
- State
- Published
- Severity
- 6.9 Medium
- Published
- Jul 30, 2026
- Updated
- Jul 30, 2026
- Reserved
- Jul 7, 2026
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.2, the WebSocket client accepts and decompresses frames with the RSV1 bit set even when the permessage-deflate extension was not negotiated, allowing a malicious server to cause unexpected CPU and memory consumption. This issue is fixed in version 3.14.2.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.9 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-20 Improper Input Validation
Affected Products
| Product | Versions |
|---|---|
aiohttpaio-libs |
|
References
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