CVE-2025-11678 HIGH

CVE-2025-11678: Stack-based Buffer Overflow in libwebsockets DNS response parsing

Vendor Warmcat
Product libwebsocket
Weakness CWE-121
Published October 20, 2025
Last update October 20, 2025
View on NVD All CVEs

CVSS base score

7.5/10
Attack vector Adjacent
Attack complexity Low
Privileges required None
User interaction —
Confidentiality —
Integrity —

CVSS vector

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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

October 20, 2025 CVE published
October 20, 2025 Record updated