nanoMODBUS through v1.23.0 contains an out-of-bounds write in the Modbus server-side handle_read_file_record function (FC 0x14, Read File Record) in nanomodbus.c. The function validates that the total request size does not exceed 245 bytes and that each sub-request's record_length is at most 124, but it never validates the CUMULATIVE response size across all sub-requests before processing them.
{
"cna_assigner": "TuranSec",
"cwe_ids": [
"CWE-787"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71254.json"
}{
"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"
}
]
}