How to Implement Network Persistent Threats in NS2

To implement the Advanced Persistent Threats (APTs) in Network Simulator 2 (NS2), we have to replicate cautious and long-terms network interruptions where an attacks profits unauthorized access to a network and remains unidentified for a prolonged period. It focuses on the data theft, espionage and generating disruptions which ignoring identification. In NS2, APTs requires generating actual attack vectors, continuous observing and network defense techniques like intrusion detection and prevention. We have offered the details on how to establish these threats in the network using ns2:

Key Aspects of Simulating APTs:

  1. Stealthy Network Intrusion: Simulating undetected access to network resources.
  2. Data Exfiltration: Silently transmitting sensitive data from the network to the attacker.
  3. Reconnaissance and Lateral Movement: Dispatching laterally in the network to gain further access.
  4. Continuous Monitoring: Identifying anomalies and abnormal activities that denote the presence of an APT.
  5. Incident Response and Mitigation: Blocking, isolating, or observing the APT once detected.

Steps to Implement Advanced Persistent Threats (APTs) in NS2:

  1. Define Network Topology:

Begin by stating a network topology that has several clients, servers, and routers. The attacker will imitate an APT by initially gaining access to one of the nodes and carrying out reconnaissance to travel laterally inside the network.

Example Tcl script for network topology:

set ns [new Simulator]

# Define network nodes: clients, servers, and attacker

set client1 [$ns node]

set client2 [$ns node]

set server1 [$ns node]  ;# Database server

set server2 [$ns node]  ;# Web server

set attacker [$ns node]  ;# Attacker (APT node)

# Define links between clients, servers, and the attacker

$ns duplex-link $client1 $server1 10Mb 10ms DropTail

$ns duplex-link $client2 $server2 10Mb 10ms DropTail

$ns duplex-link $attacker $server1 10Mb 10ms DropTail

The attacker node denotes the APT, which will stealthily perform operations on server1 (the database server) and try to move to server2 (the web server) devoid of detection.

  1. Simulate Stealthy Network Intrusion:

Simulate the attacker’s stealthy access to the network by producing less and undetected traffic amongst the attacker and the targeted servers. The attacker’s traffic should blend with normal network traffic to evade triggering alarms.

Example of simulating stealthy traffic:

# Create TCP agent for the attacker to communicate with server1 (stealthy)

set tcp_attack [new Agent/TCP]

set sink_attack [new Agent/TCPSink]

$ns attach-agent $attacker $tcp_attack

$ns attach-agent $server1 $sink_attack

$ns connect $tcp_attack $sink_attack

# Simulate low-rate, stealthy traffic (data exfiltration) from attacker to server1

set app_attack [new Application/Traffic/CBR]

$app_attack attach-agent $tcp_attack

$app_attack set packetSize_ 64  ;# Small packets to avoid detection

$app_attack set rate_ 100Kb     ;# Low traffic rate for stealth

$ns at 1.0 “$app_attack start”

The attacker node makes small amounts of traffic to ignore raising suspicions, slowly exfiltrating data from server1.

  1. Simulate Data Exfiltration and Lateral Movement:

Once the attacker gains access to server1, they can try to exfiltrate sensitive data and forward laterally to server2 (or other nodes) for further reconnaissance and attacks.

Example of simulating data exfiltration and lateral movement:

# Simulate data exfiltration from server1 to the attacker

set app_exfiltration [new Application/Traffic/CBR]

$app_exfiltration attach-agent $tcp_attack

$app_exfiltration set packetSize_ 128  ;# Data packets to exfiltrate

$app_exfiltration set rate_ 500Kb     ;# Stealthily exfiltrate data

$ns at 3.0 “$app_exfiltration start”

# Simulate lateral movement to server2

set tcp_lateral [new Agent/TCP]

set sink_lateral [new Agent/TCPSink]

$ns attach-agent $attacker $tcp_lateral

$ns attach-agent $server2 $sink_lateral

$ns connect $tcp_lateral $sink_lateral

# Attacker attempts to move laterally to server2 for further attacks

set app_lateral [new Application/Traffic/CBR]

$app_lateral attach-agent $tcp_lateral

$app_lateral set packetSize_ 64  ;# Stealthy packets for lateral movement

$app_lateral set rate_ 100Kb     ;# Low traffic rate for stealth

$ns at 5.0 “$app_lateral start”

In this example, the attacker first exfiltrates data from server1, then attempts to move laterally to server2 to continue reconnaissance and further attacks.

  1. Implement Anomaly-Based Detection (Intrusion Detection System – IDS):

Configure continuous observing of network traffic to identify anomalies like unusual traffic volumes, packet sizes, or unauthorized access attempts that might represent the presence of an APT.

Example of monitoring traffic for anomalies:

# Monitor traffic and detect anomalies

set tracefile [open apt_detection_log.tr w]

$ns trace-all $tracefile

# Detect unauthorized access to server2 by the attacker

if {$attacker_access_server2 == true} {

puts “Anomaly detected: attacker moving laterally to server2”

}

The IDS continuously observes traffic and logs any suspicious or abnormal activities like the attacker’s lateral movement from server1 to server2.

(a) Heuristic and Behavioral Detection:

Mimic detection in terms of traffic patterns that deviate from normal activities like small and reliable packet sizes or low traffic rates developed to evade detection.

Example of heuristic detection:

# Detect suspicious traffic patterns (e.g., consistent small packet sizes)

if {$packet_size == 64 && $traffic_rate == 100Kb} {

puts “Suspicious traffic pattern detected, possible APT activity”

}

This script observes for particular actions like repeated small packets or low traffic rates, which might signify a stealthy APT.

(b) Signature-Based Detection:

If the APT uses known malware or exploits, imitate signature-based detection by comparing traffic signatures to known attack patterns.

Example of signature-based detection:

# Detect known APT signature (simulated)

if {$traffic_signature == “APT_pattern”} {

puts “APT detected based on traffic signature”

}

This strategy flags traffic that matches a known attack signature, denoting the presence of a certain APT.

  1. Simulate Long-Term Persistence and Data Exfiltration:

APTs usually maintain long-term access to the network and occasionally exfiltrate data. Simulate this by having the attacker remain active over time, exfiltrating data at breaks.

Example of periodic data exfiltration:

# Simulate long-term data exfiltration at intervals

$ns at 10.0 “$app_exfiltration start”  ;# Start exfiltration

$ns at 20.0 “$app_exfiltration start”  ;# Continue exfiltration

$ns at 30.0 “$app_exfiltration start”  ;# Exfiltrate more data

The attackers occasionally exfiltrates data to evades detection by producing continuous traffic mixing with regular network activity.

  1. Implement Incident Response:

Once an APT is identified, simulate network defenses like isolating the compromised node, congesting the attacker’s traffic, or logging suspicious activity for further analysis.

Example of incident reaction to detected APT:

# Quarantine attacker after detecting unauthorized lateral movement

if {$apt_detected == true} {

puts “APT detected, isolating attacker”

set filter [new Agent/Null]

$ns attach-agent $server2 $filter

$ns connect $attacker $filter  ;# Block attacker from accessing server2

}

The attacker is congested from accessing additional network resources after their lateral movement is detected, preventing further damage.

  1. Enable Traffic Logging and Monitoring:

Enable trace files to log all network events like packet transmissions, receptions, and suspicious activities. These logs are vital for spotting APT activities and designing reports for security analysis.

Example of enabling trace logging:

set tracefile [open apt_activity_log.tr w]

$ns trace-all $tracefile

All traffic is logged for later analysis to identify APT activities includes data exfiltration, lateral movement, and long-term persistence.

  1. Visualize APT Activity Using NAM:

NAM (Network Animator) is used to envision the APT’s activities involve lateral movement, data exfiltration, and network defense replies like isolation and blocking.

Example of enabling NAM visualization:

$ns namtrace-all [open apt_simulation.nam w]

NAM can help you monitor how the attacker travels inside the network, exfiltrates data, and how network guardes respond.

  1. Generate Reports and Analyze APT Detection and Response:

After executing the simulation, generate a report detailing:

  • APT Detection: Instances where the APT was identified by the IDS or heuristic detection mechanisms.
  • Lateral Movement and Data Exfiltration: How long the APT remained undetected and how much data was exfiltrated.
  • Incident Response: The effectiveness of incident response measures like isolation, blocking, and logging.
  • Recommendations for Improvement: Suggestions for optimizing detection and defense features.

In the above process, we have presented you the step-by-step guide on how to implement a Network Advanced Persistent Threat (APT) simulation in the ns2 environment with examples. If you have any doubts regarding this, we will help you out.

Check out ns2project.com for some really cool project ideas about Network Persistent Threats using the ns2 tool! Just let us know what you need, and our team will help you with performance analysis in the best way possible. We focus on creating real attack strategies, keeping an eye on things, and using network defense methods like intrusion detection and prevention that relate to your project.