Buffer overflow in Lwip
CVE-2026-112062
lwIP through 2.2.1 contains a stack out-of-bounds write vulnerability in mdns_handle_response that allows adjacent attackers to corrupt stack memory by sending mDNS responses with invalid domain names. Attackers on the local link can send multicast PTR answers with oversized RDLENGTH or SRV answers with RDLENGTH below 6 during a service search, overflowing a 256-byte stack buffer and crashing the device.
Vulnerability class: Buffer Overflow
Published .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@haindpwn/lwip-mdns-search-result-domain-oob-write (third-party-advisory)
- github.com/lwip-tcpip/lwip/commit/ab2f69c7d8980c01cdd67ed4b23ac61118ed0205 (patch)
- github.com/lwip-tcpip/lwip/blob/STABLE-2_2_1_RELEASE/src/apps/mdns/mdns.c (technical-description)
- www.vulncheck.com/advisories/lwip-through-2.2.1-stack-out-of-bounds-write-via-m… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-112062?
- CVE-2026-112062 is a medium-severity vulnerability in Lwip, classified under Stack-based Buffer Overflow. CVSS score: 5.9/10. Published 2026-10-18.
- How severe is CVE-2026-112062?
- Medium severity. CVSS v3 base score is 5.9 out of 10.