The WiKI-Eve attack uses the Wi-Fi signal to intercept numeric passwords with an 85% success rate. Here’s how it works and how to protect yourself.
The good news: the WiKI-Eve attack, which intercepts passwords via the Wi-Fi signal, is for now a laboratory test confined to academia. The less good one: WiKI-Eve once again puts us in front of the high vulnerability of passwords that are too simple, pushing us to reflect on how much a conscious approach to cybersecurity is increasingly necessary.
Because it’s WiKI-Eve
WiKI-Eve is a real-time attack that aims to intercept the Wi-Fi signal generated when you type a password from mobile devices such as smartphones and tablets.
The attack can be carried out when an application is accessed, exploiting the so-called BFI functionality, i.e. Beamforming Feedback Information, introduced with Wi-Fi5 (802.11ac) in 2013. BFI actually has a purpose very practical as it allows devices to communicate their position to the routers to which they are connected, allowing the latter to direct the signal more accurately.
How does WiKI-Eve intercept passwords?
WiKI-Eve exploits a critical aspect of the BFI functionality: the exchange of information is not encrypted but takes place in the clear, and this means that the information can be intercepted even without the use of professional hardware.
With the use of software packet-sniffingIn fact, the hacker can identify a mobile device that is communicating its position to the network by tracing its MAC address, a unique identifier made up of two parts, the first of which allows obtaining the details of the manufacturer of the smart device or card of network. In this way a potential cyber attacker can trace the device he intends to attack among all those connected to a specific Wi-Fi network.
Every time you type something on the virtual keyboard of a smartphone, the router’s antenna produces a distinctive Wi-Fi signal, which can vary slightly depending on which keys are pressed. With the help of a Machine Learning algorithm called 1-D Convolutional Neural Network – the same one used for processing signals in electrocardiograms – the attack is able to recognize pressed keys, or the movement of fingers in the case of swipe sequences, when entering a password.
How dangerous is the WiKI-Eve attack?
The success rate of the attack is remarkable: with 6-digit numeric passwords, WiKI-Eve manages to identify the code in 85% of cases in less than a hundred attempts, an apparently important number for a human mind, but processable in a fraction of a second for a machine. The success rate is reduced for longer passwords.
The distance of the device to be attacked from the source of the Wi-Fi signal is also fundamental: a distance of 10 meters from the router leads to a success rate of no more than 23%.
Although, as anticipated at the beginning, WiKI-Eve is in fact a sort of road test, the fact that it exploits a vulnerability in the Wi-Fi connection could represent a problem in contexts such as those of smart-homewhich rely on IoT to function optimally.
Cybersecurity and passwords: how to defend yourself from cyber attacks
Greater cybersecurity starts with passwords. The general tendency, in academic environments but often also in Public Administration, is unfortunately still to rely on short numerical combinations that are easy to deduce – such as dates of birth or simple progressive sequences – with consequent exposure to greater risks in the case of an attack computer scientist. Here are a few simple rules for defend yourself appropriately and avoid unpleasant surprises.
1. Never choose passwords made up only of numbers or letters
It is enough to refer to some basic notions of combinatorics to realize how much the difficulty in stealing a password can increase or decrease with the simple difference of a digit.
In a four-digit numeric password, the possible combinations are 10,000, while with a five-digit password there are 100,000 combinations. Numbers like that, however, don’t represent much effort for a calculator.
For this reason it is always advisable to use alphanumeric passwords: a six-character alphanumeric password allows the creation of over 2 billion combinations.
To further increase security, alternate uppercase and lowercase letters and add special characters – for example exclamation points, at signs or underscores – . the possible combinations increase exponentially
A simple 8 lowercase character password can be cracked instantly. Inserting a capital letter brings the time required for interception to 22 minutes, which rises to one hour if you enter a number and 8 hours if you also use a special character. A 10-character password consisting of numbers and letters with at least one uppercase letter and one special character can keep you safe for about 5 years. If the total number of characters reaches 12, the password can be considered truly secure.
2. Don’t store passwords in easily accessible places
If possible, passwords should be stored in documents that are not easy to access, perhaps by relying on specialized managers, able to offer greater security of their data, particularly when information to be protected is used at work or in shared environments.
3. Use data encryption protocols
Avoiding connecting to public Wi-FI and making use of networks with security protocols is another fundamental step to defend yourself from cyber attacks.
Currently the most widespread protocols for the security of Wi-Fi connections are WPA2-PSK (AES) and WPA3-PSK (SAE), which use different types of encryption and are easily activated even by non-experts.
Another precaution is to use a secure keyboard. These are special keyboards in which the layout of the keys is different every time a password is typed: it is easy to understand how this can put a system like WiKI-Eve into difficulty, which relies mainly on the signal relating to the individual keys to intercept passwords of users.
