FortiSIEM Rules

Multiple Distinct IPS Events From Same Src

Rule ID

PH_Rule_IPS_1

Default Status

Enabled

Description

Detects multiple distinct IPS events from the same source IP in a short period of time - the source IP may have been infected

Severity

9

Category

Security

MITRE ATT&CK® Tactics

Execution

Execution consists of techniques that result in adversary-controlled code running on a local or remote system. Techniques that run malicious code are often paired with techniques from all other tactics to achieve broader goals, like exploring a network or stealing data. For example, an adversary might use a remote access tool to run a PowerShell script that does Remote System Discovery.

https://attack.mitre.org/tactics/TA0002

MITRE ATT&CK® Techniques

No Technique Specified

Impacts

Network

Data Source

FortiGate via Syslog, FortiProxy via Syslog, Checkpoint IPS-1 via LEA/Syslog, PaloAlto PAN-OS via Syslog

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.

DistinctIPSEvents

SubPattern Definitions

SubPattern Name: DistinctIPSEvents

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 "Checkpoint-ips" OR eventType CONTAIN "Cisco_IPS" OR
	  eventType CONTAIN "Corero-SmartWall" OR eventType CONTAIN "FortiGate-ips-" OR
	  eventType CONTAIN "Juniper_IDP" OR eventType CONTAIN "McAfee-Intrushield" OR
	  eventType CONTAIN "Forcepoint-NGFW-" OR eventType CONTAIN "Snort-") AND eventSeverity >= 7

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

srcIpAddr

Aggregate Constraint

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

COUNT (DISTINCT eventType) >= 3

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

 srcIpAddr = DistinctIPSEvents.srcIpAddr,
 incidentCount = DistinctIPSEvents.COUNT (DISTINCT eventType)