FortiSIEM Rules

System Exploit Detected by Network IPS

Rule ID

PH_Rule_ADV_20

Default Status

Enabled

Description

Detects an IPS detected exploit (e.g. Buffer overflow, Privilege escalation) optionally preceded by a Reconnaissance

Severity

7

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

Server

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.

600 seconds

Trigger Conditions

If the following defined pattern/s occur within a 600 second time window.

Reconn FOLLOWED_BY Attack

Global Constraint

This defines how two or more distinct events are related in a time-series based action. e.g. An event occurs followed by another event if the source IP, user, and messageId are the same

Reconn.destIpAddr = Attack.destIpAddr

SubPattern Definitions

SubPattern Name: Reconn

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 IN (Group@PH_SYS_EVENT_Reconn)

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,destIpAddr

Aggregate Constraint

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

COUNT(*) >= 1
Operator Rank: 0 Operator Type: FOLLOWED_BY

This operator defines the logic condition relating to the prior event subpattern clause and the following event subpattern clause

SubPattern Name: Attack

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

reptDevIpAddr IN (Group@PH_SYS_DEVICE_NETWORK_IPS) AND
	  eventType IN (Group@PH_SYS_EVENT_BufferOverflowExploit, Group@PH_SYS_EVENT_CommandExecExploit)

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,destIpAddr,eventType,ipsSignatureId

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

 srcIpAddr = Reconn.srcIpAddr,
 destIpAddr = Attack.destIpAddr,
 compEventType = Attack.eventType,
 ipsSignatureId = Attack.ipsSignatureId