{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-54410", "assignerOrgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "state": "PUBLISHED", "assignerShortName": "TuranSec", "dateReserved": "2026-06-13T16:39:46.122Z", "datePublished": "2026-06-14T17:10:12.275Z", "dateUpdated": "2026-06-14T17:10:12.275Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "shortName": "TuranSec", "dateUpdated": "2026-06-14T17:10:12.275Z"}, "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-193", "description": "CWE-193 Off-by-one Error", "type": "CWE"}]}, {"descriptions": [{"lang": "en", "cweId": "CWE-787", "description": "CWE-787 Out-of-bounds Write", "type": "CWE"}]}], "impacts": [{"descriptions": [{"lang": "en", "value": "A remote unauthenticated attacker who can reach a Modbus/TCP server built on nanoMODBUS can send a crafted MBAP frame with the Length field set to 255 to overflow the 260-byte receive buffer by one byte, corrupting the adjacent buf_idx field of the nmbs_t struct with an attacker-controlled value. This yields denial of service (subsequent handler calls treat the corrupted buf_idx as a register count / offset and crash, hang, or return invalid data), one-byte information disclosure on bare-metal and RTOS targets without memory protection (ARM Cortex-M, ESP32, STM32 class), and the possibility of writing to unintended register addresses on the FC16 (Write Multiple Registers) handler path. No authentication, no user interaction, and no special configuration are required."}]}], "affected": [{"vendor": "debevv", "product": "nanoMODBUS", "collectionURL": "https://github.com/debevv/nanoMODBUS", "repo": "https://github.com/debevv/nanoMODBUS", "programFiles": ["nanomodbus.c"], "programRoutines": [{"name": "recv_msg_header"}], "versions": [{"status": "affected", "version": "0", "lessThanOrEqual": "1.23.0", "versionType": "semver"}], "defaultStatus": "unknown"}], "descriptions": [{"lang": "en", "value": "nanoMODBUS through v1.23.0 contains an off-by-one buffer overflow in the recv_msg_header() function of the Modbus/TCP server that allows remote unauthenticated attackers to write one attacker-controlled byte past the end of the 260-byte receive buffer by sending a crafted MBAP frame whose Length field is set to 255. The overflow corrupts the adjacent buffer-index field of the nanoMODBUS state structure, resulting in denial of service through invalid memory accesses and, on bare-metal and RTOS targets without memory protection, one-byte information disclosure and writes to unintended register addresses on the Write Multiple Registers (FC16) handler path.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p>nanoMODBUS through v1.23.0 contains an off-by-one buffer overflow in the recv_msg_header() function of the Modbus/TCP server that allows remote unauthenticated attackers to write one attacker-controlled byte past the end of the 260-byte receive buffer by sending a crafted MBAP frame whose Length field is set to 255. The overflow corrupts the adjacent buffer-index field of the nanoMODBUS state structure, resulting in denial of service through invalid memory accesses and, on bare-metal and RTOS targets without memory protection, one-byte information disclosure and writes to unintended register addresses on the Write Multiple Registers (FC16) handler path.</p>"}]}], "references": [{"url": "https://github.com/debevv/nanoMODBUS", "name": "nanoMODBUS - upstream repository (vendor)", "tags": ["product"]}, {"url": "https://github.com/debevv/nanoMODBUS/blob/v1.23.0/nanomodbus.c#L369", "name": "Vulnerable bounds check at nanomodbus.c line 369 (v1.23.0)", "tags": ["product"]}, {"url": "https://cwe.mitre.org/data/definitions/193.html", "name": "CWE-193: Off-by-one Error", "tags": ["technical-description"]}, {"url": "https://cwe.mitre.org/data/definitions/787.html", "name": "CWE-787: Out-of-bounds Write", "tags": ["technical-description"]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "An attacker who can reach the TCP listening port of a Modbus/TCP server built on nanoMODBUS (typically TCP/502 on industrial / OT networks) sends a single crafted MBAP frame with Length=255 to corrupt the buf_idx field of the nmbs_t struct, causing denial of service or, on memory-protection-less embedded targets, additional information disclosure or unintended register writes."}], "cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subAvailabilityImpact": "NONE", "exploitMaturity": "PROOF_OF_CONCEPT", "Safety": "NOT_DEFINED", "Automatable": "YES", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "HIGH", "baseScore": 7.8, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:P/AU:Y"}}, {"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "HIGH", "baseSeverity": "HIGH", "baseScore": 8.6, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H"}}, {"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV2_0": {"version": "2.0", "accessVector": "NETWORK", "accessComplexity": "LOW", "authentication": "NONE", "confidentialityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "availabilityImpact": "COMPLETE", "baseScore": 9, "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:C"}}], "credits": [{"lang": "en", "value": "Burxonov Muslimbek", "type": "finder"}], "source": {"discovery": "EXTERNAL"}, "x_generator": {"engine": "Vulnogram 1.0.2"}, "x_author": "Burxonov Muslimbek", "x_assigner_notes": "Vendor 'debevv' is a single-maintainer GitHub account; nanoMODBUS is MIT-licensed. The vulnerable bounds check was verified by source inspection of v1.22.0, v1.22.1, and v1.23.0 (latest at publish time) - the issue is present in all three; affected range is therefore 0 through v1.23.0 (inclusive) with defaultStatus 'unknown' pending vendor confirmation of a fixed release. CVSS scoring follows the submitter's CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H = 8.6) and translates to 4.0 with VC:L/VI:L/VA:H, SC/SI/SA:N (= 8.7) and 2.0 with C:P/I:P/A:C (= 9.0)."}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "nanoMODBUS through v1.23.0 contains an off-by-one buffer overflow in the recv_msg_header() function of the Modbus/TCP server that allows remote unauthenticated attackers to write one attacker-controlled byte past the end of the 260-byte receive buffer by sending a crafted MBAP frame whose Length field is set to 255. The overflow corrupts the adjacent buffer-index field of the nanoMODBUS state structure, resulting in denial of service through invalid memory accesses and, on bare-metal and RTOS targets without memory protection, one-byte information disclosure and writes to unintended register addresses on the Write Multiple Registers (FC16) handler path."}], "id": "CVE-2026-54410", "lastModified": "2026-06-14T18:17:20.330", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "HIGH", "cvssData": {"accessComplexity": "LOW", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "COMPLETE", "baseScore": 9.0, "confidentialityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:C", "version": "2.0"}, "exploitabilityScore": 10.0, "impactScore": 8.5, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.6, "baseSeverity": "HIGH", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 4.7, "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "YES", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "PROOF_OF_CONCEPT", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary"}]}, "published": "2026-06-14T18:17:20.330", "references": [{"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "url": "https://cwe.mitre.org/data/definitions/193.html"}, {"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "url": "https://cwe.mitre.org/data/definitions/787.html"}, {"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "url": "https://github.com/debevv/nanoMODBUS"}, {"source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "url": "https://github.com/debevv/nanoMODBUS/blob/v1.23.0/nanomodbus.c#L369"}], "sourceIdentifier": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-193"}, {"lang": "en", "value": "CWE-787"}], "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c", "type": "Secondary"}]}

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