What ports should be blocked on the firewall to prevent NetBIOS traffic from not coming...

To block NetBIOS and related Windows networking traffic from traversing a firewall (especially from external sources), you should block the following ports:

Port 135 (TCP/UDP): Microsoft RPC endpoint mapper (DCOM/RPC)

Port 139 (TCP): NetBIOS Session Service

Port 445 (TCP): Direct-hosted SMB over TCP/IP (Windows 2000+)

These ports are commonly used for:

File sharing

RPC-based communication

Windows network services

From CEH v13 Official Courseware:

Module 3: Scanning Networks

Module 4: Enumeration

CEH v13 Study Guide states:

“To prevent external enumeration, remote file sharing, and NetBIOS attacks, administrators should block inbound access to ports 135, 139, and 445 on the firewall.”

Incorrect Options:

A (110): POP3 mail service

D (161): SNMP

F (1024): High ephemeral port; not specific to NetBIOS