CVE
CVE-2026-71256
nanoMODBUS Client-Side Out-of-Bounds Read Leading to Wild-Pointer Write via object_id
nanoMODBUS through v1.23.0 contains an out-of-bounds stack read leading to a wild-pointer write in nmbsreaddeviceidentificationbasic / recvreaddeviceidentificationres in nanomodbus.c. A fixed 3-element stack array order[3] = {0,1,2} maps object IDs to buffer indices. The server-supplied objectid field (0-255, read directly from the wire) is used without any bounds check as bufindex = order[object_id].
Package Versions Affected
Package Version
patch Availability
No items found.
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.8
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
C
H
U
-
Related Resources
No items found.
References
https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71256.json, https://github.com/debevv/nanoMODBUS, https://github.com/debevv/nanoMODBUS/blob/master/nanomodbus.c, https://nvd.nist.gov/vuln/detail/CVE-2026-71256