Deck 19: Securing Linux

Question 1

Buffer overflow attacks have become less prevalent with the growth of the Internet.

Answer 1

False

Question 2

A computer cannot be completely safeguarded from DoS attacks.

Answer 2

True

Question 3

Basing access control on IP addresses rather than hostnames makes authentication faster because you don't have to resolve hostnames.

Answer 3

True

Question 4

The htpasswd command is installed by default.

Question 5

Files and file system security are the most important aspects of data security.

Question 6

When security vulnerabilities are detected in Linux, it's up to ____ to find a solution.

A) IBM
B) Microsoft
C) McAfee Security
D) development and user communities

Question 7

____ attacks involve overloading a server with an overwhelming amount of network traffic so that it can't handle legitimate requests for network services.

A) Brute-force
B) Session hijacking
C) Address spoofing
D) Denial-of-service (DoS)

Question 8

A ____ attack is a simple attack in which ICMP Echo Request packets are sent to a victim, who continues to send packets in response, effectively choking available bandwidth.

A) ping flood
B) teardrop
C) session hijacking
D) buffer overflow

Question 9

Address spoofing is most often used on ____ firewalls.

A) stateless
B) packet-filter
C) application proxy gateway
D) circuit level relay

Question 10

____ programs are hidden scripts embedded in seemingly legitimate programs that are authorized by the unsuspecting victims.

A) Session hijacking
B) Address spoofing
C) CGI script
D) Trojan

Question 11

Session hijacking is a specialized form of ____ in which a hijacker gets unauthorized control of a network session.

A) ping flooding
B) address spoofing
C) denial-of-service (DoS)
D) CGI scripting

Question 12

____ attacks take place by guessing passwords and keys.

A) Session hijacking
B) Address spoofing
C) Denial-of-service (DoS)
D) Brute-force

Question 13

To enable or disable services, you can use the ____ module.

A) TCP Wrapper
B) YaST System Services (Runlevel)
C) xinetd daemon
D) umask

Question 14

Every computer contains a(n) ____ to send and receive data from other computers over a network.

A) network interface card (NIC)
B) firewall
C) TCP Wrapper
D) NIS module

Question 15

When put in ____ mode, a NIC receives all packets on a network, including packets destined for other computers.

A) open
B) active
C) promiscuous
D) clear

Question 16

All processes running on a computer must be monitored periodically with the ____ command to check for rogue or malfunctioning processes.

A) mn
B) pr
C) ps
D) show

Question 17

Packet sniffers are ____ and don't generate much traffic.

A) passive
B) promiscuous
C) closed
D) static

Question 18

____ is a protocol used to ensure that data transmitted to and from a remote computer is encrypted and secure.

A) Secure Shell (SSH)
B) RPC
C) SMTP
D) FTP

Question 19

Which value in the /etc/pam.d/sshd file causes the entire stack to fail if the module's demands aren't met, but only after the entire stack has been processed?

A) Required
B) Requisite
C) Sufficient
D) Optional

Question 20

The OpenSSH daemon is ____.

A) tcpd
B) xinetd
C) sshd
D) httpd

Question 21

What is the daemon for running Apache Web Server?

A) Tcpd
B) Xinetd
C) Sshd
D) Httpd

Question 22

Intranets are private ____ for transmitting data only inside the internal network.

A) local area networks (LANs)
B) wide area networks (WANs)
C) metropolitan area networks (MANs)
D) system area networks (SANs)

Question 23

Broadcast packets are ____ packets sent to every computer on a network.

A) UDP
B) IP
C) TCP
D) SMPT

Question 24

You use the ____ command to specify default file and directory permissions, which can have a major impact on a server's security when files are created.

A) ps
B) dir
C) umask
D) mask

Question 25

Permissions are granted or removed based on three types of users, ____.

A) users, groups and others
B) clients, servers, managers
C) administrators, users, others
D) administrators, users, managers

Question 26

Given the sample file permission mask, AAABBBCCCDDD, which bits represents read, write, and execute permissions for a group, with the same octal values as for user permissions?

A) AAA
B) BBB
C) CCC
D) DDD

Question 27

____________________ (CGI) scripts are used to generate a dynamic Web page's contents and can be written in a number of programming languages, such as Java, C, and Perl.

Question 28

In a(n) ____________________, data that has exceeded a buffer's storage capacity overflows into another buffer.

Question 29

____________________ developed by Wietse Venema, is a widely used tool that logs connections and is used to allow or deny access to network services.

Question 30

A(n) ____________________ is a program that captures and views packets as they're transmitted over a network.

Question 31

____________________ (PAM) provides a centralized mechanism for authenticating services.

Question 32

Match each statement with an item

-Allows users to log in to remote computers and interact with them over a secure network connection.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 33

Match each statement with an item

-Allows users to transfer files across a network with FTP.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 34

Match each statement with an item

-Allows Windows systems to share files and printers with Linux systems.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 35

Match each statement with an item

-Allows users to print jobs on a print server.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 36

Match each statement with an item

-Allows users to share file system or directory structures over a network.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 37

Match each statement with an item

-Sends identical received characters back to the sender.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 38

Match each statement with an item

-Allows users to access a remote computer's command shell without entering a login password.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 39

Match each statement with an item

-Allows users to log in to remote computers and interact with them via a terminal window.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 40

Match each statement with an item

-Gives information about local computers or users to remote computers.

A) ftp
B) telnet
C) lpd
D) finger
E) nfs
F) sshd
G) smb
H) echo
I) rlogin

Question 41

How are Common Gateway Interface (CGI) script intrusions implemented and prevented?

Question 42

Describe how session hijacking works and how it is prevented.

Question 43

Compare brute-force attacks and dictionary attacks.

Question 44

Explain how packet sniffers can be used for both good and bad.

Question 45

Explain why you would use the ps -aux command.

Question 46

Why was the free derivative of Secure Shell (SSH) created?

Question 47

Describe the two steps an NFS client can use to access files on a remote NFS server.

Question 48

Describe one method to secure NFS.

Question 49

How can you change the order of authentication in Apache Web Server?

Question 50

What is the purpose of the Masquerading section of the YaST Firewall module?