Performing Wireless Security Assessment with Kismet

Overview

Kismet is an open-source wireless network detector, packet sniffer, and wireless intrusion detection system (WIDS) supporting 802.11a/b/g/n/ac/ax. Unlike active scanners, Kismet operates in passive monitor mode, making it undetectable to the networks being assessed. It captures raw 802.11 frames, identifies access points, clients, probe requests, and encryption types without transmitting any packets. This skill covers deploying Kismet for comprehensive wireless security assessments, identifying rogue access points, detecting weak encryption, mapping hidden networks, and analyzing client behavior.

When to Use

• When conducting security assessments that involve performing wireless security assessment with kismet
• When following incident response procedures for related security events
• When performing scheduled security testing or auditing activities
• When validating security controls through hands-on testing

Prerequisites

• Linux system (Kali Linux, Ubuntu 22.04+) with Kismet 2023+ installed
• Wireless adapter supporting monitor mode (e.g., Alfa AWUS036ACH, TP-Link TL-WN722N v1)
• Written authorization for wireless assessment (legal requirement)
• GPS receiver (optional, for geolocation mapping)
• Target environment wireless network documentation

Core Concepts

Kismet Architecture

Kismet uses a client-server architecture:

• kismet - Main server process that captures and processes packets
• kismet_cap_linux_wifi - Capture source for Linux WiFi interfaces
• kismet_cap_linux_bluetooth - Capture source for Bluetooth
• Web UI - Browser-based interface at http://localhost:2501

Wireless Frame Types

Encryption Assessment

Workflow

Step 1: Prepare Wireless Adapter

# Identify wireless interfaces
iwconfig

# Check adapter capabilities
iw list | grep -A 10 "Supported interface modes"

# Kill processes that may interfere
sudo airmon-ng check kill

# Enable monitor mode
sudo ip link set wlan0 down
sudo iw dev wlan0 set type monitor
sudo ip link set wlan0 up

# Verify monitor mode
iw dev wlan0 info | grep type

Step 2: Configure and Launch Kismet

Edit /etc/kismet/kismet.conf:

# Data sources
source=wlan0:name=WiFi-Monitor,channel_hop=true,channel_hoprate=5/sec

# Logging configuration
log_types=kismet,pcapng
log_prefix=/opt/kismet/logs/assessment

# Enable all 802.11 channels (2.4GHz and 5GHz)
channel_hop_speed=5
channel_list=IEEE80211:1,2,3,4,5,6,7,8,9,10,11,36,40,44,48,52,56,60,64,100,104,108,112,116,120,124,128,132,136,140,149,153,157,161,165

# GPS configuration (if available)
gps=gpsd:host=localhost,port=2947

# Alert configuration
alert=ADVCRYPTCHANGE,5/min,1/sec
alert=BSSTIMESTAMP,5/min,1/sec
alert=CRYPTODROP,5/min,1/sec
alert=DISASSOCTRAFFIC,10/min,1/sec
alert=DEAUTHFLOOD,10/min,2/sec
alert=PROBENOMFP,5/min,1/sec

Launch Kismet:

# Start Kismet server
sudo kismet -c wlan0

# Access web interface
# Open browser to http://localhost:2501
# Default credentials: kismet / kismet (change immediately)

Step 3: Conduct Assessment Scans

Rogue Access Point Detection:

# Export device list via Kismet REST API
curl -u kismet:kismet http://localhost:2501/devices/summary/devices.json | \
    python3 -m json.tool > all_devices.json

# Filter for access points
curl -u kismet:kismet \
    'http://localhost:2501/devices/summary/devices.json' \

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