A vulnerability marked as critical has been reported in lwIP up to 2.2.1 . Affected is the function snmp_parse_inbound_frame of the file src/apps/snmp/snmp_msg.c of the component snmpv3 USM Handler . Performing a manipulation of the argument msgAuthenticationParameters results in stack-based buffer overflow. This vulnerability was named CVE-2026-8836 . The attack may be initiated remotely. There is no available exploit. It is suggested to install a patch to address this issue.