---
id: CVE-2026-112062
title: >-
  lwip: lwIP: Denial of Service via stack buffer overflow in mDNS response
  handling (CVE-2026-112062)
summary: >-
  A flaw was found in lwIP. An adjacent attacker on the local network can cause
  a Denial of Service (DoS) by sending specially crafted multicast Domain Name
  System (mDNS) responses with invalid domain names or record lengths.
  Processing thes…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H'
cvssSource: vendor
cwe:
  - CWE-121
vendor: Red Hat
product: lwIP
affected:
  - lwIP <= 2.2.1
published: '2026-10-18'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T09:34:49+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-112062.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-112062.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-112062'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-112062'
  - url: 'https://hackmd.io/@haindpwn/lwip-mdns-search-result-domain-oob-write'
  - url: >-
      https://github.com/lwip-tcpip/lwip/commit/ab2f69c7d8980c01cdd67ed4b23ac61118ed0205
  - url: >-
      https://github.com/lwip-tcpip/lwip/blob/STABLE-2_2_1_RELEASE/src/apps/mdns/mdns.c
  - url: >-
      https://www.vulncheck.com/advisories/lwip-through-2.2.1-stack-out-of-bounds-write-via-mdns-search-response-handler
    label: >-
      VulnCheck Advisory: lwIP through 2.2.1 Stack Out-of-Bounds Write via mDNS
      Search Response Handler
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - exploit-available
epss: 0.00356
epssPercentile: 0.29183
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-19T17:56:07.508494Z'
ingestedAt: '2026-10-18T12:41:54.059Z'
---

## Overview

A flaw was found in lwIP. An adjacent attacker on the local network can cause a Denial of Service (DoS) by sending specially crafted multicast Domain Name System (mDNS) responses with invalid domain names or record lengths. Processing these malformed packets during a service search triggers a stack-based buffer overflow, corrupting memory and causing the affected device to crash.

## Vendor advisories

- **Red Hat VEX** · updated 2026-10-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-112062.json)

**lwip: lwIP: Denial of Service via stack buffer overflow in mDNS response handling**. Released 2026-10-18, updated 2026-10-21.

Not affected:

- All currently supported Red Hat products

## Remediation

Refer to the advisory for fix availability.