UEBA Policy detects cloud upload

Rule ID

PH_Rule_UEBA_TAG_12

Default Status

Enabled

Description

FortiSIEM UEBA Policy detects cloud upload

Severity

MITRE ATT&CK® Tactics

UEBA

MITRE ATT&CK® Techniques

T1537

Transfer Data to Cloud Account

Adversaries may exfiltrate data by transferring the data, including backups of cloud environments, to another cloud account they control on the same service to avoid typical file transfers/downloads and network-based exfiltration detection.

https://attack.mitre.org/techniques/T1537

Impacts

Application

Data Source

Windows via FortiSIEM Agent with UEBA turned on

Detection

Correlation

Remediation Guidance

No remediation guidance specified

Time Window

If the following pattern or patterns match an ingested event within the given time window in seconds, trigger an incident.

600 seconds

Trigger Conditions

If the following defined pattern/s occur within a 600 second time window.

UEBA

SubPattern Definitions

SubPattern Name: UEBA

This is the named definition of the event query, this is important if multiple subpatterns are defined to distinguish them.

SubPattern Query

This is the query logic that matches incoming events

eventType = "FINS-Windows-file-read" AND resourceName REGEXP "[a-z]+:\\users\\.+\\(Dropbox|OneDrive|Google Drive)\\.+"  AND user NOT REGEXP ".*\$$|dwn-.*|dwm-.*|umfd-.*|.*SYSTEM.*|.*ANONYMOUS.*"

Group by Attributes

This defines how matching events are aggregated, only events with the same matching attribute values are grouped into one unique incident ID

hostName,domain,user,procName,activityName,resourceName

Aggregate Constraint

This is most typically a numerical constraint that defines when the rule should trigger an incident

COUNT(*) >= 1

Incident Attribute Mapping

This section defines which fields in matching raw events should be mapped to the incident attributes in the resulting incident.

The available raw event attributes to map are limited to the group by attributes and the aggregate event constraint fields for each subpattern

 hostName = UEBA.hostName,
 domain = UEBA.domain,
 user = UEBA.user,
 procName = UEBA.procName,
 activityName = UEBA.activityName,
 resourceName = UEBA.resourceName

FortiSIEM Rules