FortiSIEM Rules

Startup Config Change

Rule ID

PH_Rule_Change_5

Default Status

Enabled

Description

Detects that the configuration of a network device (router or firewall) has changed. This is achieved via logging in and keeping track of the last change

Severity

6

Category

Change

MITRE ATT&CK® Tactics

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.

https://attack.mitre.org/tactics/TA0005

MITRE ATT&CK® Techniques


T1562.004

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.

https://attack.mitre.org/techniques/T1562/004

Impacts

Network

Data Source

Any Device Config Monitoring via SSH

Detection

Correlation

Remediation Guidance

Make sure it is an authorized change

Time Window

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

1800 seconds

Trigger Conditions

If the following defined pattern/s occur within a 1800 second time window.

delta

SubPattern Definitions

SubPattern Name: delta

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 = "PH_DEV_MON_CHANGE_STARTUP_CONFIG"

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

hostIpAddr ,hostName ,addedItem ,deletedItem

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

hostIpAddr = delta.hostIpAddr,
 hostName = delta.hostName,
 addedItem = delta.addedItem,
 deletedItem = delta.deletedItem