Issues

• modbus_reply() accepts Write Multiple Coils with Byte Count larger than ceil(Quantity/8)

  stephane/libmodbus#883 · Filter by author K-ANOY opened on Sep 30, 2026

• modbus_proxy() sends responses on the RTU bus for broadcast requests

  stephane/libmodbus#880 · Filter by author K-ANOY opened on Sep 28, 2026

• Unauthenticated remote DoS via forced 500 ms block in modbus_reply() error paths

  stephane/libmodbus#874 · Filter by author Synmac05 opened on Sep 22, 2026

• implement the modbus TCP with TLS Support

  stephane/libmodbus#872 · Filter by author liuz888 opened on Sep 9, 2026

• FC22 confirmation accepts mismatched address and masks

  stephane/libmodbus#868 · Filter by author MrAlaskan opened on Jul 24, 2026

• Modbus TCP server ignores MBAP Length and leaves trailing bytes unread

  stephane/libmodbus#867 · Filter by author MrAlaskan opened on Jul 24, 2026

• Can you integrate your Modbus slave RTU library and Modbus master library On STM32F767 board?

  stephane/libmodbus#864 · Filter by author leoembeddeder opened on Jul 18, 2026

• [Windows][3.2.0] Valid SOCKET handles are incorrectly rejected by FD_SETSIZE checks

  stephane/libmodbus#863 · Filter by author sunmooncode opened on Jul 13, 2026
  1

• RTU Client Prematurely Aborts Request on Unexpected Slave Response

  stephane/libmodbus#861 · Filter by author MrAlaskan opened on Jun 22, 2026

• Support Modbus RTU over TCP?

  stephane/libmodbus#859 · Filter by author capwevan opened on Jun 9, 2026
  1

• Segfault on musl: _modbus_tcp_pi_connect calls freeaddrinfo(NULL) on getaddrinfo failure (mirror of #831)

  stephane/libmodbus#852 · Filter by author NeriaIfrah opened on May 18, 2026

• [TCP] Missing TCP_NODELAY and socket options on server-accepted connections in modbus_tcp_accept

  stephane/libmodbus#849 · Filter by author NeriaIfrah opened on May 17, 2026

• libmodbus 3.1.12 Modbus/TCP MBAP Length framing flaw causes stock request-path desynchronization and connection-level DoS

  stephane/libmodbus#848 · Filter by author gff-cw opened on May 10, 2026
  2

• Can not build with Visual Studio due GCC-style warning flags

  stephane/libmodbus#846 · Filter by author uilianries opened on May 4, 2026

• Exception function codes are constructed by adding +0x80, which may cause a wrap-around for illegal function codes.

  stephane/libmodbus#845 · Filter by author MrAlaskan opened on Apr 13, 2026

• FC 0x11 (Report Slave ID) Is Incorrectly Handled Over Modbus TCP (Serial-Line-Only Function Exposed)

  stephane/libmodbus#844 · Filter by author MrAlaskan opened on Apr 13, 2026
  1

• Slowloris-Style DoS in Modbus TCP Receive Path on Windows

  stephane/libmodbus#843 · Filter by author MrAlaskan opened on Apr 13, 2026

• libmodbus 3.1.12 does not connect in windows

  stephane/libmodbus#842 · Filter by author hdabis1234 opened on Feb 17, 2026
  1

• [Windows RTU] modbus_receive() ignores response/byte timeout unless indication_timeout is set

  stephane/libmodbus#822 · Filter by author draculamx opened on Sep 1, 2025

• Conflict with between defined const and enum.

  stephane/libmodbus#821 · Filter by author pavliqme opened on Aug 26, 2025
  2

  

• Tests are failing on slow machines or on architectures with unreliable SMP timers

  stephane/libmodbus#815 · Filter by author bigon opened on Jul 8, 2025
  1

• A violation regarding the specifications for the protocol identifier.

  stephane/libmodbus#814 · Filter by author ProtocolSpecCheck opened on Jun 30, 2025

• A bug that violates the specification of the length field

  stephane/libmodbus#810 · Filter by author jyjsunny opened on Jun 5, 2025
  1

• Compilation error with MinGW and GCC 14

  stephane/libmodbus#809 · Filter by author StalderT opened on Jun 3, 2025

• Floating point byte order does not round-trip

  stephane/libmodbus#807 · Filter by author johannes1971 opened on May 1, 2025
  3