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Open the default Audit Dashboard and scroll to the table at the bottom of the dashboard. Open one of the events where attribute "Event" is equal "true" using the triangle at the very left of the event row. You'll see all attributes, that are available for an event:
Search index with browser URL
You can also look into audit-default report using browser URLs. e.g. to look into the audit-default-2022.05.10 index enter the following command depending on your serves IP or URL and port:
https://<server URL or IP>:<port>/elasticsearch/audit-default-2022.05.10/_search?pretty
The result will look similar to the screen below. Each entry begins with "_index" and the name of the index. Attributes will start after "_source" and are marked red.
Elasticsearch URL interface
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