CVE-2026-71254 json
nanoMODBUS Server-Side Out-of-Bounds Write in handle_read_file_record()
published 2026-08-05 3 mo ago modified 2026-10-24 16 d ago also EUVD-2026-53331
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
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.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 3 mo ago
Exploit prediction
0.55% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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-2026-71254
- NVD CVE-2026-71254
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.