smbrelayx

Impacket's smbrelayx is a tool designed for performing SMB relay attacks. An SMB relay attack is a type of security exploit where an attacker intercepts and relays SMB (Server Message Block) authentication requests from one computer to another on the network. This tool is part of the Impacket suite, a collection of Python classes and tools for working with network protocols.

The primary function of smbrelayx is to relay SMB authentication sessions from one host to another. It captures the authentication request from one machine and forwards it to a second machine, effectively impersonating the first machine. smbrelayx facilitates a man-in-the-middle (MitM) position where it can intercept and manipulate SMB traffic.

One of the significant aspects of SMB relay attacks is that the attacker doesn't need to know the user's password. The tool uses the authentication session itself to gain access. Once authentication is relayed and access is gained, smbrelayx can be used to execute arbitrary commands on the target machine.

An example of how you might use Impacket's smbrelayx in a command-line environment:

python smbrelayx.py -h <TARGET_IP> -e /path/to/executable

• -h <TARGET_IP>: The IP address of the target machine where you want to relay the SMB authentication.
• -e /path/to/executable: Path to an executable file that will be run on the target machine upon successful relay.

Info

In a typical SMB relay attack scenario, the attacker would need to be in a position to intercept SMB traffic, which might involve [[ARP poisoning]] or other network manipulation techniques.