A customer reported an issue with this log info:

{{../../../mongo-c-driver-src/src/libbson/src/bson/bson.c:2239
bson_steal(): assertion failed: dst}}

That's all info we got (e.g., no dump available).

We are using the latest mongocxx (4.3.1), and do not bson_steal() anywhere.

So not sure, if the C++ layer (mongocxx) should always protect against dst being null - if so, it could be an internal issue with mongocxx.