Crowdstrike: Detection Occurred but was allowed

Rule ID

PH_Rule_Exploits_CS_22

Default Status

Enabled

Description

Crowdstrike agent detection occurred but due to policy disable or other reasons decided to allow the behavior to continue

Severity

Detection Technology

Correlation

Rule Mode

Streaming

MITRE ATT&CK® Tactics

Command and Control

Command and Control consists of techniques that adversaries may use to communicate with systems under their control within a victim network. Adversaries commonly attempt to mimic normal, expected traffic to avoid detection. There are many ways an adversary can establish command and control with various levels of stealth depending on the victim’s network structure and defenses.

https://attack.mitre.org/tactics/TA0011

MITRE ATT&CK® Techniques

No Technique Specified

Impacts

Server

Data Source

Crowdstrike via FALCON_STREAMING_API or FALCON_DATA_REPLICATOR

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.

300 seconds

Trigger Conditions

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

CSDetect

SubPattern Definitions

SubPattern Name: CSDetect

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 CONTAIN "Crowdstrike-Falcon-EppDetectionSummaryEvent-" and fwAction="allow"

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,attackTactic,attackTechnique,user,command,subtype

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 = CSDetect.hostName,
 attackTactic= CSDetect.attackTactic,
 attackTechnique= CSDetect.attackTechnique,
 user = CSDetect.user,
 command = CSDetect.command,
 subtype = CSDetect.subtype

FortiSIEM Rules