In today's digital landscape, a wireless network is critical infrastructure for any home or office, and understanding how to secure it is becoming a must-have skill.
Using the operating system Kali Linux Security analysis allows administrators and information security specialists to identify weaknesses in equipment configurations before they are exploited by attackers.
It's important to emphasize that any actions to intercept traffic or scan other people's networks without the owner's written permission are a violation of the law. Therefore, this guide is for educational purposes only and is intended to strengthen the security of your own infrastructure.
The penetration testing process requires a deep understanding of the architecture of wireless protocols such as IEEE 802.11, and the ability to correctly interpret the received data so as not to harm the operating services.
Preparation of the working environment and equipment
To get started, you will need a computer with the software installed. Kali Linux and, most importantly, a compatible wireless adapter that supports monitor mode and packet injection.
Built-in laptop cards often lack the necessary functionality or drivers, so professionals typically use external chip-based USB adapters. Atheros AR9271 or Ralink RT3070.
⚠️ Warning: Before performing any tests, ensure that you are only testing on your own equipment or have the official permission of the network owner, as illegal access to computer information is punishable by law.
After connecting the device, you need to make sure that the system has correctly identified it and installed the necessary drivers, which can be checked through the terminal.
- 🔌 Make sure your Wi-Fi adapter supports the mode
monitorfor passive listening to the broadcast. - 💻 Install the latest system updates Kali Linux through repositories to keep vulnerability databases up to date.
- 🔋 Use an uninterruptible power supply or a fully charged battery, as the scanning process can be power-intensive.
- 📡 Check for available frequencies in your area to avoid interference with critical services.
Command line in Kali provides powerful tools for managing interfaces, and the first step is always to put the card into monitor mode.
For this purpose, a utility is used airmon-ng, which automatically disables interfering processes and reconfigures the device driver.
sudo airmon-ng start wlan0After running this command, your interface will most likely be renamed to wlan0mon, which will signal readiness to work in sniffing mode.
Wireless space analysis and data collection
The first stage of the audit is reconnaissance, which involves discovering all available networks and assessing their signal strength, broadcast channels, and encryption types.
Tool airodump-ng allows you to visualize the broadcast in real time, displaying lists of access points (AP) and clients connected to them (Station).
In the resulting list, you will see columns with information about the cipher, for example WPA2 or WEP, as well as the current data transfer rate and signal strength.
To filter out noise and focus on a specific target, you need to know BSSID (MAC address) of the router and the channel number on which it operates.
Launching the sniffer with specific parameters allows you to save all passing traffic to a file for subsequent detailed analysis.
sudo airodump-ng --bssid 00:11:22:33:44:55 --channel 6 --write audit_log wlan0monDuring the data collection process, it is important to monitor customer activity, as some verification methods require a connected device.
If the network is inactive, a security professional can initiate a client disconnect process to force a reconnection and generate new handshakes.
| Parameter | Description | Importance for audit |
|---|---|---|
| BSSID | Unique MAC address of the access point | High (target ID) |
| Channel | Broadcast frequency channel | Critical (for sniffer setup) |
| ENC | Encryption type (WPA2, WPA3) | High (determines the attack method) |
| PWR | Signal strength | Medium (affects stability) |
| #Data | Number of collected data packets | High (required for analysis) |
Methods for checking password strength
After successfully capturing a 4-way handshake between the client and the router, the cryptanalysis stage begins, the purpose of which is to check the strength of the key phrase.
The most common method is offline dictionary attack, where hashes from a captured packet are compared to hashed words from a database.
Utility aircrack-ng is the industry standard for this task and supports various dictionary formats and mutation rules.
What is a WPA handshake?
A handshake is the process of exchanging keys between a client and an access point upon connection. During this process, encrypted information is transmitted, which can be decrypted with the password.
The effectiveness of this method directly depends on the quality of the dictionary used and the complexity of the password set by the user.
spruce.If the password is a simple word or a combination of dates, it can be cracked in a matter of seconds even on weak equipment.
aircrack-ng -w /usr/share/wordlists/rockyou.txt audit_log-01.capFor more complex passwords containing a random set of characters, the brute-force method is used, which theoretically can try all combinations, but requires colossal computing resources.
Modern security standards recommend using long passphrases, as increasing the length of a key exponentially increases the time required to crack it.
Using specialized automation scripts
To simplify the testing process in the arsenal Kali Linux There are wrapper scripts such as wifite2, which automate a sequence of actions.
This tool automatically scans the airwaves, selects targets, launches a handshake attack, and attempts to brute-force a password, minimizing manual operator intervention.
⚠️ Warning: Automated scripts can be aggressive and create a high load on the airwaves, which may lead to temporary disruption of legitimate devices in the coverage area.
The use of such tools is justified when conducting a quick audit of a large number of points, but requires caution in dense residential areas.
☑️ Safe Audit Plan
Scripts allow you to easily configure attack parameters, such as the handshake timeout or the signal strength threshold for cutting off remote clients.
However, I believe
By relying on automation, a specialist risks missing important details that he would have noticed during manual packet analysis.Protecting your network from unauthorized access
Understanding hacking methods allows us to formulate effective defense strategies, the first of which is to abandon outdated encryption protocols.
Protocol WEP is considered completely unsafe and should be replaced by WPA2-AES or, ideally, to a new standard WPA3, which implements protection against offline brute-force attacks.
A critical security element is the use of complex passwords of at least 12-15 characters in length, including uppercase and lowercase letters, numbers, and special characters.
- 🔐 Disable the feature WPS in the router settings, as it often contains vulnerabilities that allow password protection to be bypassed.
- 📡 Reduce the transmitter power to a level sufficient to cover the room so that the signal does not extend beyond the controlled area.
- 👥 Use a guest network to connect visitor devices and IoT gadgets, isolating them from the main infrastructure.
- 🔄 Update your router firmware regularly to patch known software security holes.
An additional security measure is MAC address filtering, although this method is not foolproof as addresses can be easily spoofed.
The most effective measure remains a combination of strong encryption, a complex password, and timely software updates.
Security Outlook: WPA3 and New Threats
With the development of security technologies, attack methods are also evolving, in particular with the introduction of the standard WPA3 The classic handshake has been replaced by the more secure SAE protocol.
Protocol Simultaneous Authentication of Equals Protects against handshake interception, making it impossible to subsequently try it offline using traditional methods.
However, researchers have already discovered vulnerabilities, such as Dragonblood-type attacks, that allow key strength to be reduced or partial password information to be recovered.
Owners of critical infrastructure are advised to begin planning their migration to WPA3-enabled equipment now.
Security professionals must study new attack vectors to stay ahead of potential attackers.
⚠️ Note: Router settings interfaces and Kali Linux tool functionality may change with the release of new versions, so always check the manufacturer's official documentation.
Understanding the fundamental principles of network operation allows you to adapt to any changes in software.
Frequently Asked Questions (FAQ)
Is it legal to use Kali Linux to test your Wi-Fi?
Yes, testing the security of your own networks, or networks that you have official written permission to audit from the owner, is a completely legal and recommended action to improve your security.
Is it possible to crack WPA3 using standard dictionaries?
No, standard dictionary attacks against a captured handshake do not work on WPA3 due to the use of the SAE protocol, which prevents offline attacks on password hashes.
Which adapter is best for Kali Linux?
The best compatibility and support for all functions (including packet injection) are demonstrated by adapters based on Atheros AR9271, Ralink RT3070, and Realtek RTL8812AU chips.
How long does it take to crack a Wi-Fi password?
The time it takes to crack a password varies from a few seconds for simple passwords to millions of years for complex keys, and depends on the password length, the dictionary used, and the computing power of the hardware.