CVE-2026-71254 (GCVE-0-2026-71254)

Vulnerability from cvelistv5 – Published: 2026-08-05 11:44 – Updated: 2026-08-10 11:46
VLAI
Title
nanoMODBUS Server-Side Out-of-Bounds Write in handle_read_file_record()
Summary
nanoMODBUS through v1.23.0 contains an out-of-bounds write in the Modbus server-side handle_read_file_record function (FC 0x14, Read File Record) in nanomodbus.c. The function validates that the total request size does not exceed 245 bytes and that each sub-request's record_length is at most 124, but it never validates the CUMULATIVE response size across all sub-requests before processing them.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-05 12:29 UTC
CWE
Assigner
TuranSec CNA under the mitre root
CNA scorecard C 70/100 over 189 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
debevv nanoMODBUS Affected: 0 , ≤ 1.23.0 (semver)
guessed Create a notification for this product.
Date Public
2026-08-05 11:44
Credits
Shukhratbek Uraiimov
Show details on NVD website
To clipboard 

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