{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-71256", "assignerOrgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "state": "PUBLISHED", "assignerShortName": "TuranSec", "dateReserved": "2026-08-05T11:43:52.778Z", "datePublished": "2026-08-05T11:44:21.992Z", "dateUpdated": "2026-08-10T11:46:18.081Z" }, "containers": { "cna": { "title": "nanoMODBUS Client-Side Out-of-Bounds Read Leading to Wild-Pointer Write via object_id", "descriptions": [ { "lang": "en", "value": "nanoMODBUS through v1.23.0 contains an out-of-bounds stack read leading to a wild-pointer write in nmbs_read_device_identification_basic / recv_read_device_identification_res in nanomodbus.c. A fixed 3-element stack array order[3] = {0,1,2} maps object IDs to buffer indices. The server-supplied object_id field (0-255, read directly from the wire) is used without any bounds check as buf_index = order[object_id].", "supportingMedia": [ { "type": "text/html", "base64": false, "value": "
nanoMODBUS through v1.23.0 contains an out-of-bounds stack read leading to a wild-pointer write in nmbs_read_device_identification_basic / recv_read_device_identification_res in nanomodbus.c. A fixed 3-element stack array order[3] = {0,1,2} maps object IDs to buffer indices. The server-supplied object_id field (0-255, read directly from the wire) is used without any bounds check as buf_index = order[object_id].
" } ] } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "description": "CWE-125", "cweId": "CWE-125", "type": "CWE" } ] } ], "affected": [ { "vendor": "debevv", "product": "nanoMODBUS", "programFiles": [ "nanomodbus.c" ], "versions": [ { "version": "0", "lessThanOrEqual": "1.23.0", "status": "affected", "versionType": "semver" } ], "defaultStatus": "unaffected" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH" } } ], "references": [ { "url": "https://github.com/debevv/nanoMODBUS", "tags": [ "third-party-advisory" ] }, { "url": "https://github.com/debevv/nanoMODBUS/blob/master/nanomodbus.c", "tags": [ "third-party-advisory" ] } ], "credits": [ { "lang": "en", "value": "Shukhratbek Uraiimov", "type": "finder" } ], "providerMetadata": { "orgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "shortName": "TuranSec", "dateUpdated": "2026-08-10T11:46:18.081Z" }, "source": { "discovery": "EXTERNAL" }, "datePublic": "2026-08-05T11:44:21.992Z" }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-08-05T12:25:23.617290Z", "id": "CVE-2026-71256", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-08-05T12:26:11.018Z" } } ] } }