CVE-2026-59881 (GCVE-0-2026-59881)

Vulnerability from cvelistv5 – Published: 2026-07-30 17:34 – Updated: 2026-07-30 18:35
VLAI
Title
AIOHTTP: WebSocket client accepts compressed frames without negotiated permessage-deflate
Summary
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.
Severity
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-30 18:35 UTC
CWE
  • CWE-20 - Improper Input Validation
Assigner
References
Impacted products
Vendor Product Version
aio-libs aiohttp Affected: < 3.14.2
Create a notification for this product.
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