CVE-2026-71255CWE-787

CVE-2026-71255

High · published August 5, 2026

CVSS v3.1

8.6

EPSS

Percentile

31.4

In the wild

Unconfirmed

What it is

nanoMODBUS through v1.23.0 contains an out-of-bounds write in the Modbus client-side recv_read_device_identification_res function (FC 0x2B/MEI 0x0E, Read Device Identification) in nanomodbus.c. The server-supplied object_length field (0-246) is validated only against the remaining PDU size (res_size_left) and is never validated against the caller-supplied buffers_length parameter.

The record

Technical detail

CVSS v3.1: 8.6 · HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
CVSS v4.0: Not supplied
EPSS: 0.00385 · 31.4th percentile
Weakness: CWE-787 · Out-of-bounds Write
Published: 2026-08-05T16:18Z

References (2)

https://github.com/debevv/nanoMODBUS · 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c https://github.com/debevv/nanoMODBUS/blob/master/nanomodbus.c · 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c

EPSS history

Timeline

05 AUG 11:44Z
nanoMODBUS Client-Side Out-of-Bounds Write via object_length in recv_read_device_identification_res()
cvelistv5