github.com/panther-labs/stix2 (go): Package stix2 is a pure Go library for working with Structured Threat Information Expression (STIX™) version 2.x data.  Parsing STIX JSON data:  Creating a STIX Bundle, is as easy as creating a set of STIX objects and add them to the Collection. The Bundle can be created by calling the `ToBundle` method on the Collection object. The Bundle can be serialized to `JSON` using the `JSON` encoder in the standard library.  Example of a malware using an infrastructure. Taken from: https://docs.oasis-open.org/cti/stix/v2.1/csprd02/stix-v2.1-csprd02.html#_Toc26789941  With the release of version 2.1 of the specification custom properties has been deprecated. Instead, `property-extension` functionality should be used. This library supports parsing objects with old custom properties for backwards compatibility. The fields can be accessed via the `GetExtendedTopLevelProperties` method.  See the examples on how to work with extensions.
Keywords: golang|security