from logs-o365.audit-*
| where
event.dataset == "o365.audit" and
event.provider == "OneDrive" and
event.action == "FileDownloaded" and
o365.audit.AuthenticationType == "OAuth" and
event.outcome == "success"
and (user.id is not null and o365.audit.ApplicationId is not null)
| eval session.id = coalesce(o365.audit.AppAccessContext.AADSessionId, session.id, null)
| where session.id is not null
| eval Esql.time_window_date_trunc = date_trunc(1 minutes, @timestamp)
| stats
Esql.file_directory_values = values(file.directory),
Esql.file_extension_values = values(file.extension),
Esql.application_name_values = values(application.name),
Esql.file_name_count_distinct = count_distinct(file.name),
Esql.o365_audit_Site_values = values(o365.audit.Site),
Esql.o365_audit_SiteUrl_values = values(o365.audit.SiteUrl),
Esql.user_domain_values = values(user.domain),
Esql.token_id_values = values(token.id),
Esql.event_count = count(*)
by
Esql.time_window_date_trunc,
user.id,
session.id,
source.ip,
o365.audit.ApplicationId
| where Esql.file_name_count_distinct >= 25
| keep
Esql.*,
user.id,
source.ip,
o365.audit.ApplicationId,
session.id
Install detection rules in Elastic Security
Detect M365 OneDrive Excessive File Downloads with OAuth Token in the Elastic Security detection engine by installing this rule into your Elastic Stack.
To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).