CVE-2026-71255 json
nanoMODBUS Client-Side Out-of-Bounds Write via object_length in recv_read_device_identification_res()
published 3mo ago modified 18d ago also EUVD-2026-53332
- cvss
- 8.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 33%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 3mo ago
Exploit prediction
0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H |
Affected products
- debevv nanoMODBUS
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
github.com
/debevv/nanoMODBUS
third-party-advisory
-
github.com
/debevv/nanoMODBUS/blob/master/nanomodbus.c
third-party-advisory
Sources
- CVE List CVE-2026-71255
- NVD CVE-2026-71255
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