CVE-2025-11680

MEDIUM

libwebsockets 4.0-4.4.1 and 4.3.0-4.3.5 - Out-of-bounds Write in unfilter_scanline via Crafted PNG Width

Title source: llm
STIX 2.1

Description

Out-of-bounds Write in unfilter_scanline in warmcat libwebsockets allows, when the LWS_WITH_UPNG flag is enabled during compilation and the HTML display stack is used, to write 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 width value that causes an integer overflow which value is used for determining the size of a heap allocation.

References (2)

Core 2

Scores

CVSS v4 5.9
EPSS 0.0036
EPSS Percentile 27.3%
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/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-787
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