Mosquitto 1.6.7 has been released, this is a bugfix release.


  • Add workaround for working with libwebsockets 3.2.0.
  • Fix potential crash when reloading config. Closes #1424, #1425.

Client library

  • Don't use / in autogenerated client ids, to avoid confusing with topics.
  • Fix mosquitto_max_inflight_messages_set() and mosquitto_int_option(..., MOSQ_OPT_*_MAX, ...) behaviour. Closes #1417.
  • Fix regression on use of mosquitto_connect_async() not working. Closes #1415 and #1422.


  • mosquitto_sub: Fix -E incorrectly not working unless -d was also specified. [Closes #1418].
  • Updated documentation around automatic client ids.