CVE-2026-71255
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.
SeverityHigh
CVSS8.6
Exploit probability—
ProductnanoMODBUS
PublishedAug 5, 2026
First seenAug 5, 2026
Weakness typeCWE-787Out-of-bounds write
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| debevv nanoMODBUS | v ≤ 1.23.0 | — |
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