Use After Free in libwebsockets WebSocket server_CVE-2025-11677

6.3 / 10

MEDIUM

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

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.

Basic Information

ID CVE-2025-11677

Source Nozomi

Published Oct 20, 2025 at 13:41

Modified Oct 20, 2025 at 13:54

Affected Product

Vendor warmcat

Product libwebsockets

Version 4.0

Affected Versions warmcat libwebsockets 4.0
warmcat libwebsockets 4.0

CWE Classification

CWE-416

References

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    "published": "2025-10-20T13:41:10.787Z",
    "modified": "2025-10-20T13:54:19.569Z",
    "type": "cve",
    "title": "Use After Free in libwebsockets WebSocket server",
    "source": "Nozomi",
    "references": "https://libwebsockets.org/git/libwebsockets/commit?id=2f082ec31261f556969160143ba94875d783971a\nhttps://www.nozominetworks.com/labs/vulnerability-advisories-cve-2025-11677",
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