Detect Threats Based on Abnormal Behavior Instead of Signatures

Business Scenario

You are a SOC Analyst at CyberSecure Solutions. The organisation wants to detect threats that may not have known signatures.

Your task is to observe normal system behaviour, identify unusual activities, investigate them, and determine whether they could indicate a security threat.

 

Pre-Lab Preparation

Topic: Incident Response and Investigation 

1) Introduction to SIEM tools such as Splunk and Wazuh

2) Alert triaging and investigation process

3) Threat detection techniques

Git Pull

git pull origin branchName

Objective

Create a baseline of normal system activity.

Task 1: Understand Normal Behavior 

Open the SIEM dashboard.

1

Select the test endpoint.

2

Review normal events over a defined period.

3

Record:

4

  • Normal login times

  • Normal users

  • Normal processes

  • Normal network activity

  • Normal resource usage

  • Normal login times

  • Normal users

  • Normal processes

  • Normal network activity

  • Normal resource usage

Create a simple baseline.

5

Example

Expected Output

 

Activity

Students create a basic baseline of normal behaviour. 

Objective

Detect activity that differs from the established baseline.

Review the SIEM for activities such as:

 

Task 2: Identify Abnormal Behavior

Multiple failed logins.

1

Log in at an unusual time.

2

Unexpected privileged activity.

3

Unknown process execution.

4

Unusual network connections.

5

Sudden large amounts of file activity.

6

Example

Expected Output

 

Compare the activity with the normal baseline.

 

Activity

Students identify at least one abnormal behaviour.

Objective

Determine whether the abnormal behaviour represents a potential threat.

Select the suspicious event.

1

Review related logs.

2

Check:

3

Task 3: Investigate the Anomaly

  • Username

  • Source IP

  • Timestamp

  • Host

  • Process/activity

Compare it with normal behaviour.

4

Determine whether the activity is:

5

  • Normal

  • Suspicious

  • Potential Incident

Expected Output

 

Activity

Students provide evidence supporting their decision.

Task 4: Detect Without Using a Signature 

Objective

Understand how behavior can reveal threats even when no known signature exists.

Select a suspicious behaviour pattern.

1

Identify the characteristics of the behavior.

2

Create a simple detection condition based on behavior.

3

Example

The detection should focus on what happened, rather than the name or signature of known malware.

Expected Output

 

Activity

Students create a simple behaviour-based detection scenario.

Objective

Respond to a suspicious behavioral anomaly.

Review the severity of the finding.

1

Select an appropriate response in the test environment.

2

For example:

3

Task 5: Apply a Defensive Response 

  • Disable a test account.

  • Reset test credentials.

  • Isolate a test endpoint.

  • Investigate the suspicious process.

Continue monitoring the system.

4

Verify whether the abnormal behavior stops.

5

Expected Output

 

Activity

Students demonstrate a basic detect → investigate → respond workflow.

Task 6: Document the Finding 

Objective

Create a basic behaviour-based detection report.

Record:

 

FieldExample
Finding IDBEHAV-001
BehaviorUnusual Login
UserTest User
Normal BehaviorLogin during working hours
Observed BehaviorLogin at unusual time
SeverityMedium
AnalysisBehavior differs from baseline
ActionAccount investigated
StatusInvestigating
FieldExample
Finding IDBEHAV-001
BehaviorUnusual Login
UserTest User
Normal BehaviorLogin during working hours
Observed BehaviorLogin at unusual time
SeverityMedium
AnalysisBehavior differs from baseline
ActionAccount investigated
StatusInvestigating

Example Finding

 

Finding:

Abnormal User Behaviour

 

Observation:

A test account performed activity outside its normal

behaviour pattern.

 

Analysis:

The activity differed from the established baseline

and was investigated using related SIEM events.

 

Risk:

The behaviour may indicate compromised credentials

or unauthorised activity.

 

Recommendation:

Continue monitoring the account and investigate

related authentication and endpoint events.

Example Finding

 

Finding:

Abnormal User Behaviour

 

Observation:

A test account performed activity outside its normal

behaviour pattern.

 

Analysis:

The activity differed from the established baseline

and was investigated using related SIEM events.

 

Risk:

The behaviour may indicate compromised credentials

or unauthorised activity.

 

Recommendation:

Continue monitoring the account and investigate

related authentication and endpoint events.

Expected Output

 

 

Great job!

After completing this lab, students will be able to explain proactive threat hunting, create hunting hypotheses, search logs without relying on alerts, identify suspicious patterns, investigate potential threats, map findings to the MITRE ATT&CK framework, and document threat-hunting activities effectively.

Checkpoint

   Git Push

git push origin branchName

Next-Lab Preparation

Topic: Log Management and Analysis

1) Introduction to SIEM tools such as Splunk and Wazuh

2) Alert triaging and investigation process

3) Threat detection techniques

Copy of SOC 01 - Perform Proactive Threat Hunting Instead of Reactive Monitoring

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Copy of SOC 01 - Perform Proactive Threat Hunting Instead of Reactive Monitoring

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