---
id: CVE-2025-11678
title: "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 ord…"
summary: "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 ord…"
severity: none
cwe:
  - CWE-121
published: '2025-10-20'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T22:10:00.563'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-11678'
references:
  - url: >-
      https://libwebsockets.org/git/libwebsockets/commit?id=2bb9598562b37c942ba5b04bcde3f7fdf66a9d3a
    label: prodsec@nozominetworks.com
  - url: >-
      https://www.nozominetworks.com/labs/vulnerability-advisories-cve-2025-11678
    label: prodsec@nozominetworks.com
tags:
  - nvd
epss: 0.00285
epssPercentile: 0.19296
ingestedAt: '2026-10-08T22:11:53.816Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.