Questions about how to access someone else's network often arise from users concerned about their own security. A theoretical understanding of the processes used to penetrate Wi-Fi is the foundation for building a robust perimeter defense for your home or corporate network. Console interface Linux operating systems provide administrators with powerful tools for analyzing traffic and identifying weak points.
Attempting unauthorized access to a computer network without the owner's knowledge is a criminal offense in many jurisdictions. This article is for informational purposes only. educational character The aim of this project is to demonstrate the vulnerabilities of encryption protocols for subsequent mitigation. We will examine the technical aspects of wireless interface operation in monitoring mode and the principles of handshake interception.
Understanding the mechanics of attacks allows you to properly configure your router and select strong encryption algorithms. The only reliable method of protection is to use the WPA3 or WPA2 protocol with a long random password that cannot be brute-forced in a reasonable amount of time. Ignoring basic cyber hygiene rules turns your network into an open book for anyone with a laptop.
⚠️ Warning: Any scanning or testing of other people's networks without the owner's written permission may be considered a violation of the law. Use these methods only on your own equipment!
Necessary equipment and environment preparation
To conduct a wireless network security audit, a standard office laptop running Windows is not enough. You will need a computer running the operating system Linux (For example, Kali Linux or Parrot OS) and a wireless adapter that supports packet monitoring and injection. Most modules built into laptops Wi-Fi They only work in client mode and do not allow interception of the entire broadcast.
The key element is the compatibility of the adapter chipset with the drivers mac80211The most popular and time-tested devices are those based on chips. Atheros AR9271, Ralink RT3070 or Realtek RTL8812AUThese models allow the card to be switched to a mode in which it ceases to be just a receiver and becomes a fully-fledged spectrum analyzer.
The preparation process includes installing the necessary drivers and checking for support for the required functions. Kernel modules often need to be compiled manually, which requires basic console skills. Without properly configured hardware, further analysis steps are impossible. security protocols will be impossible.
- 📡 External USB Wi-Fi adapter with monitor mode support
- 💻 A laptop or PC with a Linux distribution installed
- 🔌 USB extender to improve antenna signal reception
- 📱 Smartphone to check your network availability after tests
⚠️ Important: When purchasing an adapter, be sure to check the list of supported chipsets on the community forums, as manufacturers often change the internals of devices without changing the case model.
Setting up the wireless interface in monitor mode
The first step in the audit process is to put the network interface into monitor mode. Normally, the card ignores packets addressed to other devices, but in monitor mode monitor Forces it to pass all traffic to the operating system for analysis. This allows you to see not only your network data but also your neighbors' signals, access points, and hidden SSIDs.
To manage interfaces in Linux, a set of utilities is most often used aircrack-ngBefore starting work, you must stop processes that may conflict with the network card, such as NetworkManager or wpa_supplicantAfter stopping the services, the interface is disabled and switched to the desired mode using the command iw or a specialized utility airmon-ng.
A successful transition is confirmed by a change in the interface name, to which a suffix is often added monThe device is now ready for passive listening. It's important to understand that in this mode, the card doesn't connect to access points, but merely registers passing radio waves.
sudo airmon-ng start wlan0As a result of executing the command, a new interface will appear in the list, for example, wlan0monThis is what we'll be working on further. If errors occur, the driver may not support injections, and the adapter will need to be replaced.
Analysis of the surrounding ether and target selection
Once the monitoring mode is activated, the reconnaissance phase begins. Utility airodump-ng Allows you to visualize all wireless networks within range. The screen displays a list of access points with information about the channel, signal strength, encryption type, and the number of connected clients.
To test your own security, you need to find your network in the list by MAC address or name (SSID). Pay attention to the column ENC, which specifies the encryption type. If it is specified there OPN, the network is open. If WPA2 or WPA3 — protection is active. We're interested in networks with active encryption, as they require password strength testing.
An important parameter is the signal level (PWR). The closer the value is to zero (for example, -40), the stronger the signal. To successfully intercept a handshake, you must be in a strong reception area. A weak signal will result in packet loss and the inability to complete the audit process.
| Parameter | Description | Value for the test |
|---|---|---|
| BSSID | MAC address of the access point | Unique router identifier |
| PWR | Signal level | The smaller the negative number, the better. |
| ENC | Encryption type | WPA2, WPA3 (WEP is obsolete) |
| MBR | Maximum speed | Depends on the 802.11 standard |
What are hidden networks?
Hidden networks do not broadcast their name (SSID), but continue to send control frames. They appear in the list as
WPA/WPA2 Handshake Capture
The essence of an attack on modern networks is not to crack encryption on the fly, which is practically impossible for strong algorithms, but to intercept the authentication process. When a device connects to Wi-Fi, a key exchange occurs, called handshake (handshake). This exchange contains a password hash that can be cracked offline.
To record a handshake, you need to run airodump-ng specifying a specific channel and BSSID of the target network. The program will begin saving packets to a file. However, waiting for someone to connect to the network voluntarily can be an endless process. Therefore, security administrators use deauthentication.
Team aireplay-ng Allows the router to send a special control frame to the connected client's address on behalf of the router. Upon receiving this frame, the client assumes the connection has been lost and automatically attempts to reconnect. At this point, a new handshake occurs, which is captured by the sniffer.
sudo aireplay-ng -0 5 -a [Router_BSSID] -c [Client_MAC] wlan0monIn the program log airodump-ng an inscription will appear in the upper right corner WPA Handshake: [MAC Address]This means the goal has been achieved and the file with the selection data has been saved. Further work can now be carried out without the wireless card.
Password selection and strength analysis
The resulting handshake file contains the hashes, but not the cleartext password itself. A brute-force or dictionary attack is used to recover the original text. The utility aircrack-ng takes a file with a hash and compares it with the hashes of words from a text dictionary file.
The effectiveness of this method directly depends on the complexity of the password and the computing power of the hardware. If the password is a simple word or a date of birth, it can be found in seconds. However, random combination A system of 12 or more characters, including numbers and special characters, can take centuries to create, even on powerful clusters.
There are specialized dictionaries containing millions of frequently used passwords and mutation rules that modify words (replacing 'a' with '@', appending numbers to the end). This significantly speeds up the search process, but against truly complex keys, such methods are useless.
- 📂 rockyou.txt — a classic dictionary of 14 million passwords
- ⚡ Hashcat — a GPU-based brute-force tool
- 📜 Custom rules — rules for changing words to expand your vocabulary
- 🖥️ CPU vs. GPU — GPUs speed up brute-force searches hundreds of times
⚠️ Note: The speed of brute-force attacks depends on the hashing algorithm. WPA2 uses PBKDF2, which is deliberately slow to make brute-force attacks more difficult, unlike faster hashes like MD5.
Methods for protecting your home network
Understanding the vulnerabilities described above allows us to formulate clear protection rules. First and foremost, it is necessary to abandon the use of the protocol WEP, which can be hacked in minutes, and even WPA/TKIPThe only relevant standard today is WPA2-AES or, ideally, WPA3, if your hardware supports it.
Password length and complexity are crucial. An 8-character password can be brute-forced in a reasonable amount of time. Increasing the length to 15-20 characters makes brute-force attacks cost- and time-ineffective. Use passphrases—long phrases that are easy to remember but difficult to guess.
An additional security measure is to disable the function WPS (Wi-Fi Protected Setup). This protocol, which allows connection via a PIN code or push-button, has critical implementation vulnerabilities that allow the PIN code to be recovered within a few hours and the network password to be discovered.
☑️ Router security check
Regularly updating your router firmware patches software vulnerabilities that could allow attackers to access the admin panel. Don't neglect this simple step, as manufacturers frequently release patches for critical vulnerabilities.
FAQ: Frequently Asked Questions
Is it possible to hack Wi-Fi from an Android phone?
This is theoretically possible, but requires root access and a special external adapter connected via OTG. Built-in smartphone modules rarely support packet injection, which is necessary for full-fledged auditing.
How long does it take to crack a password?
The time depends on the complexity. A simple password (for example, "12345678") can be cracked instantly. A complex password of 12+ random characters can take thousands of years to crack, even on powerful equipment.
Will hiding your SSID protect you from being hacked?
No. Hiding the network name doesn't encrypt traffic or hide the network itself from sniffers. It's merely an inconvenience for legitimate users, but a minor obstacle for attackers.
Is WPS mode dangerous?
Yes, the WPS protocol has fundamental design vulnerabilities. It is recommended to completely disable this feature in your router settings, even if you only use the connect button.