MS 365 Defender: System Network Configuration Discovery - Discovery Alert

Rule ID

PH_RULE_MS_DefEndpoint_Alert_Discov_NetConfigDiscovery

Default Status

Enabled

Description

System Network Configuration Discovery - Discovery Alert from MS 365 Defender

Severity

MITRE ATT&CK® Tactics

Discovery

Discovery consists of techniques an adversary may use to gain knowledge about the system and internal network. These techniques help adversaries observe the environment and orient themselves before deciding how to act. They also allow adversaries to explore what they can control and what’s around their entry point in order to discover how it could benefit their current objective. Native operating system tools are often used toward this post-compromise information-gathering objective.

https://attack.mitre.org/tactics/TA0007

MITRE ATT&CK® Techniques

T1016.001

System Network Configuration Discovery: Internet Connection Discovery

Adversaries may check for Internet connectivity on compromised systems. This may be performed during automated discovery and can be accomplished in numerous ways such as using [Ping](https://attack.mitre.org/software/S0097), tracert, and GET requests to websites.

https://attack.mitre.org/techniques/T1016/001

Impacts

Network

Data Source

MS 365 Defender via HTTPS_ADVANCED (Graph API) ,Azure Event Hub via AZURE_PYTHON_SDK

Detection

Correlation

Remediation Guidance

Investigate the alert and determine if the observed behavior was legitimate.

Time Window

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

300 seconds

Trigger Conditions

If the following defined pattern/s occur within a 300 second time window.

ms_defender_alert

SubPattern Definitions

SubPattern Name: ms_defender_alert

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 = "MS-Defender-Endpoint-Alert-Discovery" OR eventType CONTAIN "M365Defender-Alert") AND  attackTechniqueId = "T1016"

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

alertIdStr,alertName,tenantId

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

 alertName=ms_defender_alert.alertName,
alertIdStr=ms_defender_alert.alertIdStr,
tenantId=ms_defender_alert.tenantId,
incidentCount=ms_defender_alert.COUNT(*)

FortiSIEM Rules