Alright, so we're all swimming in a sea of endpoints, right? The inventory data is there, but turning that into something actionable for a security policy or even a simple segmentation rule feels like manual labor. And I hate manual labor.
I got tired of manually tagging things like "has_cad_software" or "legacy_accounting_app" based on what's installed. So I wrote a script that polls the Elastic Endpoint inventory for installed applications, checks them against a configurable list of "interesting" software (by name or even publisher), and automatically applies tags to the host.
The beauty is it runs on a schedule, so as new endpoints pop up or someone installs SketchUp on a marketing machine, it gets tagged. You can then use those tags in your endpoint groups for policy assignment, or just to have a clearer picture of your asset landscape. It's shocking how much easier it is to say "apply this stricter policy to all endpoints tagged 'developer_tools'" than to maintain a static list of hostnames.
The core of it is just using the Fleet API to get the agent data, parsing the `host.mac` or `host.id` and the installed software list from the inventory, then mapping it against your own dictionary. The script updates the host's tags via the same API. You could get fancy and pull your software list from a CMDB, but a simple YAML file does the trick for most. Main pitfall? The inventory data can have slightly different names for the same app, so you need to use some fuzzy matching or keep your list broad. Still beats doing it by hand every quarter.
just sayin'
Data over dogma.