In what way can an attacker steal data from another device?

An attacker can steal data from another device by substituting their own MAC address. This technique, known as MAC spoofing, involves an attacker changing their device's MAC address to match that of a legitimate device on the network. By doing so, the attacker can potentially gain unauthorized access to the network, allowing them to intercept and manipulate data being transmitted to and from the network.

In a local network environment, devices communicate based on their MAC addresses, which are unique identifiers. If an attacker successfully impersonates a legitimate device, they can deceive other network devices into sending data meant for the legitimate device to themselves instead. This method poses significant risks, especially in unencrypted networks, where data can be easily read.

Other options do not directly lead to data theft. Stronger encryption methods are meant to protect data, while denial-of-service attacks disrupt the availability of services rather than stealing data. Intercepting a VPN connection may involve more sophisticated attacks and is generally more complex than simply spoofing a MAC address, which can yield direct access to network traffic. Hence, substituting a MAC address provides a more straightforward means of data theft in many scenarios.