CVE-2026-71263 (GCVE-0-2026-71263)

Vulnerability from cvelistv5 – Published: 2026-08-05 12:26 – Updated: 2026-08-10 11:46
VLAI
Title
FreeModbus LINUXTCP Port Off-by-One Global Buffer Overflow in xMBPortTCPPool()
Summary
The LINUXTCP port of FreeModbus contains an off-by-one bounds check in xMBPortTCPPool (demo/LINUXTCP/port/porttcp.c). The check uses a strict greater-than comparison instead of greater-than-or-equal against the 263-byte MB_TCP_BUF_SIZE limit.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-05 15:39 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
cwalter-at FreeModbus Affected: 0 , ≤ * (custom)
guessed Create a notification for this product.
Date Public
2026-08-05 12:26
Credits
Alibek Baxtiyorov
Show details on NVD website
To clipboard 

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