I'd start with the content you are feeding QRadar with.
Do you have any IPS/IDS or WAF that sends logs to QRadar? Is it configured to track for such events?
There are Windows event IDs that can be used to track user account changes (4720=created, 4738=changed, 4726=delected, 4722=enabled, 4725=disabled). How did you configure Windows auditing? It should be easy to track based on these IDs or associated QIDs. Question is what do you want to achieve : generally monitor (could be e.g. a good case to save a search and create a report) or monitor for particular usernames (e.g. add the names to a reference set and have a rule that tracks the QIDs for these events and username matching the items in the ref. set) or something else?
Did you integrate MySQL with QRadar already? I recall there was a need to download MySQL driver for JDBC ( https://www.ibm.com/support/pages/qradar-how-download-and-install-mysql-driver-jdbc-log-source ). How did you configure the auditing on MySQL side? Do you e.g. have the events related to user creation/deletion? Are there needed details in the log that relate to the specific roles/tables/etc?
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Dusan VIDOVIC
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