CVE-2026-54410

Summary

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.

Affected Software

VendorProductVersion RangeStatus
debevvnanoMODBUS0 <= 1.23.0affected

Weaknesses

  • CWE-193: CWE-193 Off-by-one Error
  • CWE-787: CWE-787 Out-of-bounds Write

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References