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Enumerating SMB and NFS

Cyber Security Mastery: From Zero to Hero

Finding Shared Resources

SMB and NFS are network protocols used for sharing files and printers. Misconfigured shares often expose sensitive data or provide an easy entry point for attackers.

SMB (Server Message Block) - Windows

SMB runs on TCP ports 139 and 445.

  • Tool: smbclient or enum4linux (Kali tool).
  • Goal: Identifying shares accessible by guest/anonymous users, listing user accounts, and determining the OS version.

bash

Check for null session access (anonymous access)

smbclient -L 192.168.1.100 -N

NFS (Network File System) - Linux

NFS allows file sharing between Unix/Linux systems.

  • Tool: showmount (Kali tool).
  • Goal: Listing which directories are being exported by the target server and which IP addresses are permitted to mount them.

bash showmount -e 192.168.1.100

If shares are misconfigured to allow 'world' access, attackers can dump files or potentially introduce malicious executable files.