{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-54410: nanoMODBUS through v1","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-54410","status":"final","version":"1","initial_release_date":"2026-06-14T17:10:12.275Z","current_release_date":"2026-06-14T17:10:12.275Z","revision_history":[{"date":"2026-06-14T17:10:12.275Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"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.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-54410 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-54410"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-54410"},{"category":"external","summary":"nanoMODBUS - upstream repository (vendor)","url":"https://github.com/debevv/nanoMODBUS"},{"category":"external","summary":"Vulnerable bounds check at nanomodbus.c line 369 (v1.23.0)","url":"https://github.com/debevv/nanoMODBUS/blob/v1.23.0/nanomodbus.c#L369"},{"category":"external","summary":"CWE-193: Off-by-one Error","url":"https://cwe.mitre.org/data/definitions/193.html"},{"category":"external","summary":"CWE-787: Out-of-bounds Write","url":"https://cwe.mitre.org/data/definitions/787.html"}]},"product_tree":{"branches":[{"category":"vendor","name":"debevv","branches":[{"category":"product_name","name":"nanoMODBUS","branches":[{"category":"product_version_range","name":"<=1.23.0","product":{"name":"debevv nanoMODBUS <=1.23.0","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:debevv:nanomodbus:*:*:*:*:*:*:*:*"}}}]}]}]},"vulnerabilities":[{"cve":"CVE-2026-54410","title":"nanoMODBUS through v1","notes":[{"category":"description","text":"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.","title":"CVE description"}],"product_status":{"known_affected":["CSAFPID-1"]},"scores":[{"cvss_v4":{"version":"4.0","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","baseScore":7.8,"baseSeverity":"HIGH"},"products":["CSAFPID-1"]}],"remediations":[{"category":"none_available","details":"No fixed version is published yet. Monitor the upstream advisory.","product_ids":["CSAFPID-1"]}]}]}