CVE-2025-11679

MEDIUM

libwebsockets - Buffer Overflow

Title source: llm
STIX 2.1

Description

Out-of-bounds Read in lws_upng_emit_next_line in warmcat libwebsockets allows, when the LWS_WITH_UPNG flag is enabled during compilation and the HTML display stack is used, to read past a heap allocated buffer possibly causing a crash, when the user visits an attacker controlled website that contains a crafted PNG file with a big height dimension.

References (2)

Core 2

Scores

CVSS v4 5.9
EPSS 0.0004
EPSS Percentile 13.8%
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-125
Status published
Products (2)
warmcat/libwebsockets 4.0 - 4.3.6
warmcat/libwebsockets 4.0 - 4.4.2
Published Oct 20, 2025
Tracked Since Feb 18, 2026