CVE-2026-71255

HIGH
MEDIUM Priority: 0.03 BB Relevance: 77/100
Published: 2026-08-05 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: Low
I: Low
A: High

Description

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.

Weakness Classification (1)

Bug Bounty Relevance

77 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

8.6 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H

EPSS — Exploitation Probability

0.39%
Raw Score 0.003850
Percentile 32.5%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00385
2026-10-28
0.00385

Intelligence Sources

nvd ref →