Fixes for the following CVES:
The list of other fixes addressed in version 1.5.6 is:
- Fixed comment handling for config options that have optional arguments.
- Improved documentation around bridge topic remapping.
- Handle mismatched handshakes (e.g. QoS1 PUBLISH with QoS2 reply) properly.
- Fix spaces not being allowed in the bridge remote_username option. Closes #1131.
- Allow broker to always restart on Windows when using log_dest file. Closes #1080.
- Fix Will not being sent for Websockets clients. Closes #1143.
- Windows: Fix possible crash when client disconnects. Closes #1137.
- Fixed durable clients being unable to receive messages when offline, when per_listener_settings was set to true. Closes #1081.
- Add log message for the case where a client is disconnected for sending a topic with invalid UTF-8. Closes #1144.
- Fix TLS connections not working over SOCKS.
- Don't clear SSL context when TLS connection is closed, meaning if a user provided an external SSL_CTX they have less chance of leaking references.