CVE-2026-71263

The FreeModbus LINUXTCP port has a concrete defect in xMBPortTCPPool(): the code uses a strict greater-than check (usTCPFrameBytesLeft > MB_TCP_BUF_SIZE) against a 263-byte MB_TCP_BUF_SIZE limit. When an MBAP frame with Length 264 is processed, usTCPFrameBytesLeft becomes 263, the check passes...