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.

CVSS 4.0

6.0CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

5.9CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

EPSS

0.4% chance of exploitation in the next 30 days; higher than 29% of CVEs (scores of 2026-10-25)

CWE

CWE-121

Published

2026-10-18

Modified

2026-10-19

Record from

the NVD, synced 2026-10-21

References

• https://github.com/lwip-tcpip/lwip/blob/STABLE-2_2_1_RELEASE/src/apps/mdns/mdns.c
• https://github.com/lwip-tcpip/lwip/commit/ab2f69c7d8980c01cdd67ed4b23ac61118ed0205
• https://hackmd.io/@haindpwn/lwip-mdns-search-result-domain-oob-write
• https://www.vulncheck.com/advisories/lwip-through-2.2.1-stack-out-of-bounds-write-via-mdns-search-response-handler
• https://hackmd.io/@haindpwn/cve-2026-112062-lwip-mdns-search-result-domain-oob-write

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