SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-11677

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…

MEDIUM 6.3EPSS 0.38%

Does this matter?

Lower severity and a low EPSS score (0.38%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 4.0
6.3 MEDIUMCVSS: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/M
EPSS
0.38% probability · 31th percentile
CISA KEV
Not listed
Weakness
CWE-416
Source
prodsec@nozominetworks.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.