{"id":"CVE-2026-29972","aliases":["EUVD-2026-28785","GHSA-5hc8-p74q-47pp"],"status":"published","title":"nanoMODBUS through v1.22.0 has a stack-based buffer overflow in recv_read_registers_res() in...","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.","severity":{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-11","score":0.00639,"percentile":0.5107,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-121"],"published":"2026-05-08T00:00:00Z","modified":"2026-10-28T02:31:05Z","references":[{"url":"https://github.com/debevv/nanoMODBUS","tags":["package"]},{"url":"https://github.com/debevv/nanoMODBUS/blob/master/nanomodbus.c#L580-L615","tags":["web"]},{"url":"https://gist.github.com/dwilliams27/a4e26fe747c8561d608f7549804bd85f","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-29972","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-5hc8-p74q-47pp"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29972.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-29972","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.","status":"published","published":"2026-05-08T00:00:00Z","modified":"2026-05-08T15:59:03.619Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"adp"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T14:19:56.284359Z"}],"euvd":[{"id":"EUVD-2026-28785","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.","status":"published","published":"2026-05-08T00:00:00Z","modified":"2026-05-08T15:59:03Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"updated_at":"2026-11-02T19:05:14.505765Z"}],"ghsa":[{"id":"GHSA-5hc8-p74q-47pp","title":"nanoMODBUS through v1.22.0 has a stack-based buffer overflow in recv_read_registers_res() in...","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.","status":"published","published":"2026-05-08T18:31:34Z","modified":"2026-05-08T18:31:38Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T15:07:57.635262Z"}],"nvd":[{"id":"CVE-2026-29972","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.","status":"published","published":"2026-05-08T16:16:09.96Z","modified":"2026-06-17T10:29:58.4Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-121"],"updated_at":"2026-11-02T14:12:17.842772Z"}],"osv":[{"id":"CVE-2026-29972","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.","status":"published","published":"2026-05-08T00:00:00Z","modified":"2026-10-28T02:31:05.643277399Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:00.530889Z"}]}}