FortiSIEM Rules

Linux: Attempt to Disable Crowdstrike Service

Rule ID


Default Status



Adversaries may attempt to disable the Crowdstrike HIDS service in an attempt to an attempt to disrupt detection by security controls. This requires process monitoring via FortiSIEM Linux agent.






Defense Evasion

Defense Evasion consists of techniques that adversaries use to avoid detection throughout their compromise. Techniques used for defense evasion include uninstalling/disabling security software or obfuscating/encrypting data and scripts. Adversaries also leverage and abuse trusted processes to hide and masquerade their malware. Other tactics’ techniques are cross-listed here when those techniques include the added benefit of subverting defenses.

MITRE ATT&CK® Techniques


Impair Defenses: Disable or Modify System Firewall

Adversaries may disable or modify system firewalls in order to bypass controls limiting network usage. Changes could be disabling the entire mechanism as well as adding, deleting, or modifying particular rules. This can be done numerous ways depending on the operating system, including via command-line, editing Windows Registry keys, and Windows Control Panel. Modifying or disabling a system firewall may enable adversary C2 communications, lateral movement, and/or data exfiltration that would otherwise not be allowed.



Data Source

Linux Process Monitoring via FortiSIEM Agent



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.


SubPattern Definitions

SubPattern Name: Filter

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 = "LINUX_PROCESS_EXEC" AND procName = "systemctl" AND swParam REGEXP ".*stop\s+falcon-sensor\.service.*|.*disable\s+falcon-sensor.service.*"

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, user, procName, swParam

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 = Filter.hostName,
 user = Filter.user,
 procName = Filter.procName,
 swParam = Filter.swParam