# 5.5.1

## Enhancements

- [#12497](https://github.com/emqx/emqx/pull/12497) Improved MongoDB connector performance, resulting in more efficient database interactions. This enhancement is supported by improvements in the MongoDB Erlang driver as well ([mongodb-erlang PR](https://github.com/emqx/mongodb-erlang/pull/41)).

## Bug Fixes

- [#12471](https://github.com/emqx/emqx/pull/12471) Fixed an issue that data integration configurations failed to load correctly during upgrades from EMQX version 5.0.2 to newer releases.

- [#12598](https://github.com/emqx/emqx/pull/12598) Fixed an issue that users were unable to subscribe to or unsubscribe from shared topic filters via HTTP API.

  The affected APIs include:

  - `/clients/:clientid/subscribe`
  - `/clients/:clientid/subscribe/bulk`

  - `/clients/:clientid/unsubscribe`
  - `/clients/:clientid/unsubscribe/bulk`

- [#12601](https://github.com/emqx/emqx/pull/12601) Fixed an issue where logs of the LDAP driver were not being captured. Now, all logs are recorded at the `info` level.

- [#12606](https://github.com/emqx/emqx/pull/12606) The Prometheus API experienced crashes when the specified SSL certificate file did not exist in the given path. Now, when an SSL certificate file is missing, the `emqx_cert_expiry_at` metric will report a value of 0, indicating the non-existence of the certificate.

- [#12620](https://github.com/emqx/emqx/pull/12620) Redacted sensitive information in HTTP headers to exclude authentication and authorization credentials from `debug` level logs in the HTTP Server connector, mitigating potential security risks.

- [#12632](https://github.com/emqx/emqx/pull/12632) Fixed an issue where the rule engine's SQL built-in function `date_to_unix_ts` produced incorrect results for dates starting from March 1st on leap years.

- [#12608](https://github.com/emqx/emqx/pull/12608) Fixed a `function_clause` error in the IoTDB action caused by the absence of a `payload` field in query data.

- [#12610](https://github.com/emqx/emqx/pull/12610) Fixed an issue where connections to the LDAP connector could unexpectedly disconnect after a certain period of time.