Vulnerabilidad · Publicado 05/08/2026
nanoMODBUS hasta la versión 1.23.0 contiene una vulnerabilidad de lectura fuera de los límites de la pila que permite escritura de punteros salvajes en la función nmbs_read_device_identification_basic(). Un campo object_id no validado (0-255) desde la red causa acceso a memoria no inicializada. Afecta sistemas SCADA, HMI y equipos IoT industriales en plantas manufactureras y servicios críticos de LATAM.
nanoMODBUS through v1.23.0 contains an out-of-bounds stack read leading to a wild-pointer write in nmbs_read_device_identification_basic() / recv_read_device_identification_res() in nanomodbus.c. A fixed 3-element stack array order[3] = {0,1,2} maps object IDs to buffer indices. The server-supplied object_id field (0-255, read directly from the wire) is used without any bounds check as buf_index = order[object_id]. When a malicious Modbus server sends a Read Device Identification response with object_id >= 3, this reads an out-of-bounds/garbage byte from the stack adjacent to order[], which is then used as an index into a 3-element buffers[] array of char* pointers. The resulting wild pointer is passed to strncpy() as the destination, causing an arbitrary-address write with server-controlled data.
Score: 9.8/10 — Severidad: CRITICAL — Estado NIST: Received
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-125
Publicado en NIST NVD.