CVE-2026-59881

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.

CVSS

No CVSS.

References

Link	Resource
http://github.com/aio-libs/aiohttp/releases/tag/v3.14.2
https://github.com/aio-libs/aiohttp/commit/47fb6ae354d4fa22048f4dbe7dbf82b625f0a2f6
https://github.com/aio-libs/aiohttp/pull/12978
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-mq44-7p77-q5h7

Configurations

No configuration.

History

30 Jul 2026, 19:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-30 19:18

Updated : 2026-07-30 20:03

NVD link : CVE-2026-59881

Mitre link : CVE-2026-59881

CVE.ORG link : CVE-2026-59881

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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