CVE-2025-11677

MEDIUM

libwebsockets 3-4.4.1,4.3.6 - Use-After-Free in WebSocket Server Handshake

Title source: llm
STIX 2.1

Description

Use After Free in WebSocket server implementation in lws_handshake_server in warmcat libwebsockets may allow an attacker, in specific configurations where the user provides a callback function that handles LWS_CALLBACK_HTTP_CONFIRM_UPGRADE, to achieve denial of service.

References (2)

Core 2

Scores

CVSS v4 6.3
EPSS 0.0037
EPSS Percentile 28.5%
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-416
Status published
Products (1)
warmcat/libwebsockets 3 - 4.4.1,4.3.6
Published Oct 20, 2025
Tracked Since Feb 18, 2026