VULNERABILITY INTELLIGENCE
CVE-2026-71256
CVSS score9.8 CRITICAL
EPSS probability0.55%
CISA KEVNot currently listed
Published2026-08-05
Last modified2026-10-24
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
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].
Weakness classification
- 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c: CWE-125