CVE-2025-11678

HIGH

libwebsockets 4.0-4.4.1 and 4.0-4.3.5 - Stack-based Buffer Overflow in lws_adns_parse_label

Title source: llm
STIX 2.1

Description

Stack-based Buffer Overflow in lws_adns_parse_label in warmcat libwebsockets allows, when the LWS_WITH_SYS_ASYNC_DNS flag is enabled during compilation, to overflow the label_stack, when the attacker is able to sniff a DNS request in order to craft a response with a matching id containing a label longer than the maximum.

References (2)

Core 2

Scores

CVSS v4 7.5
EPSS 0.0027
EPSS Percentile 18.4%
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/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 total

Details

CWE
CWE-121
Status published
Products (2)
warmcat/libwebsocket 4.0 - 4.3.6
warmcat/libwebsocket 4.0 - 4.4.2
Published Oct 20, 2025
Tracked Since Feb 18, 2026