CVE-2026-29972_CVE-2026-29972

8.2 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

Description

nanoMODBUS through v1.22.0 has a stack-based buffer overflow in recv_read_registers_res() in nanomodbus.c. When a client calls nmbs_read_holding_registers() or nmbs_read_input_registers(), the library writes register data from the server response to the caller-provided buffer based on the response's byte_count field before validating that byte_count matches the requested quantity. A malicious Modbus TCP server can send a response with byte_count=250 (125 registers) regardless of the requested quantity, causing up to 248 bytes of attacker-controlled data to overflow the buffer, potentially allowing remote code execution.

Basic Information

ID CVE-2026-29972

Source mitre

Published May 8, 2026 at 00:00

Modified May 8, 2026 at 15:59

Affected Product

Vendor n/a

Product n/a

Version n/a

Affected Versions n/a n/a n/a

CWE Classification

CWE-121

References

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    "published": "2026-05-08T00:00:00.000Z",
    "modified": "2026-05-08T15:59:03.619Z",
    "type": "cve",
    "title": "CVE-2026-29972",
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    "references": "https://github.com/debevv/nanoMODBUS\nhttps://github.com/debevv/nanoMODBUS/blob/master/nanomodbus.c#L580-L615\nhttps://gist.github.com/dwilliams27/a4e26fe747c8561d608f7549804bd85f",
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