CVE-2026-29972

Published: Mag 08, 2026 Last Modified: Mag 08, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 8,2
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: low
Availability: high

Description

AI Translation Available

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.

121

Stack-based Buffer Overflow

Draft
Abstraction: Variant Structure: Simple
Common Consequences
Security Scopes Affected:
Availability Integrity Confidentiality Access Control Other
Potential Impacts:
Modify Memory Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Execute Unauthorized Code Or Commands Bypass Protection Mechanism Other
Applicable Platforms
Languages: C, C++, Memory-Unsafe
Likelihood of Exploit: High
View CWE Details
https://gist.github.com/dwilliams27/a4e26fe747c8561d608f754…
https://gist.github.com/dwilliams27/a4e26fe747c8561d608f7549804bd85f
https://github.com/debevv/nanoMODBUS
https://github.com/debevv/nanoMODBUS
https://github.com/debevv/nanoMODBUS/blob/master/nanomodbus…
https://github.com/debevv/nanoMODBUS/blob/master/nanomodbus.c#L580-L615