MongoDB C Driver 1.27.0 Released

Announcing 1.27.0 of libbson and libmongoc, the libraries constituting the MongoDB C Driver.


No changes since 1.26.2. Version incremented to match the libmongoc version.



  • Raise required version of libmongocrypt to 1.10.0 to support In-Use Encryption (corresponds to the CMake option: ENABLE_CLIENT_SIDE_ENCRYPTION).
  • A future minor release plans to raise the minimum supported MongoDB Server version from 3.6 to 4.0. This is in accordance with MongoDB Software Lifecycle Schedules.


  • Fix possible crash when client is configured with empty password.

New Features:

  • Add database name to command events: mongoc_apm_command_failed_get_database_name and mongoc_apm_command_succeeded_get_database_name.
  • Support delegated KMIP protocol for In-Use Encryption.
  • Enable setting socket timeout per client.


Thanks to everyone who contributed to this release.

  • Kevin Albertson
  • Adrian Dole
  • Ezra Chung
  • Roberto C. Sánchez
  • Scott Hunt