CVE-2026-71256

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Source
https://cve.org/CVERecord?id=CVE-2026-71256
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-71256.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-71256
Published
2026-08-05T11:44:21Z
Modified
2026-10-26T02:30:29Z
Severity
  • 9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
nanoMODBUS Client-Side Out-of-Bounds Read Leading to Wild-Pointer Write via object_id
Details

nanoMODBUS through v1.23.0 contains an out-of-bounds stack read leading to a wild-pointer write in nmbs_read_device_identification_basic / recv_read_device_identification_res in nanomodbus.c. A fixed 3-element stack array order[3] = {0,1,2} maps object IDs to buffer indices. The server-supplied object_id field (0-255, read directly from the wire) is used without any bounds check as buf_index = order[object_id].

Database specific 
{
    "cna_assigner":  "TuranSec",
    "cwe_ids":  [
        "CWE-125"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71256.json"
}
References

Affected packages

Git / github.com/debevv/nanomodbus

Affected ranges

Type
GIT
Repo
https://github.com/debevv/nanomodbus
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Last Affected
91d6782930ee263bc760f27b0cbc5b82773c5f0d
Database specific
Show details 
{
    "extracted_events":  [
        {
            "range":  [
                {
                    "introduced":  "0"
                },
                {
                    "last_affected":  "1.23.0"
                }
            ],
            "source":  "AFFECTED_FIELD",
            "strategy":  "StandardRange"
        },
        {
            "range":  [
                {
                    "introduced":  "0"
                },
                {
                    "last_affected":  "1.23.0"
                }
            ],
            "source":  "DESCRIPTION"
        }
    ]
}

Affected versions

v1.*
v1.0
v1.0.0
v1.0.1
v1.1.0
v1.1.1
v1.10.0
v1.11.0
v1.12.0
v1.12.1
v1.13.0
v1.14.0
v1.14.1
v1.14.2
v1.14.3
v1.15.0
v1.16.0
v1.17.0
v1.17.1
v1.17.2
v1.17.3
v1.18.1
v1.19.0
v1.2.0
v1.2.1
v1.20.0
v1.20.1
v1.21.0
v1.22.0
v1.22.1
v1.23.0
v1.3.0
v1.3.1
v1.4.0
v1.5.0
v1.6.0
v1.7.0
v1.8.0
v1.8.1
v1.9.0
v1.9.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-71256.json"