CEH-001 Exam Dumps : Certified Ethical Hacker (CEH)

A penetration tester is conducting a port scan on a specific host. The tester found several ports opened that were confusing in concluding the Operating System (OS) version installed. Considering the NMAP result below, which of the following is likely to be installed on the target machine by the OS?

Starting NMAP 5.21 at 2011-03-15 11:06

NMAP scan report for 172.16.40.65

Host is up (1.00s latency).

Not shown: 993 closed ports

PORT STATE SERVICE

21/tcp open ftp

23/tcp open telnet

80/tcp open http

139/tcp open netbios-ssn

515/tcp open

631/tcp open ipp

9100/tcp open

MAC Address: 00:00:48:0D:EE:89

After a client sends a connection request (SYN) packet to the server, the server will respond (SYN-ACK) with a sequence number of its choosing, which then must be acknowledged (ACK) by the client. This sequence number is predictable; the attack connects to a service first with its own IP address, records the sequence number chosen, and then opens a second connection from a forged IP address. The attack doesn't see the SYN-ACK (or any other packet) from the server, but can guess the correct responses. If the source IP address is used for authentication, then the attacker can use the one-sided communication to break into the server. What attacks can you successfully launch against a server using the above technique?

What is the command used to create a binary log file using tcpdump?