NETACAD 16 NETWORK SECURITY

Question 1

Who is a threat actor?

Answer 1

Intruders who gain access by modifying software or exploiting software vulnerabilities are called threat actors.

Question 2

Describe 4 types of threats that arise after a threat actor gains access to the network

Answer 2

Information theft is breaking into a computer to obtain confidential information. Information can be used or sold for various purposes such as when someone is stealing proprietary information of an organization, like research and development data.

Data loss and manipulation is breaking into a computer to destroy or alter data records. An example of data loss is a threat actor sending a virus that reformats a computer hard drive. An example of data manipulation is breaking into a records system to change information, such as the price of an item.

Identity theft is a form of information theft where personal information is stolen for the purpose of taking over the identity of someone. Using this information, a threat actor can obtain legal documents, apply for credit, and make unauthorized online purchases. Identify theft is a growing problem costing billions of dollars per year.

Disruption of Service
Disruption of service is preventing legitimate users from accessing services to which they are entitled. Examples include denial of service (DoS) attacks on servers, network devices, or network communications links.

Question 3

What is a vulnerability?

Answer 3

Vulnerability is the degree of weakness in a network or a device. Some degree of vulnerability is inherent in routers, switches, desktops, servers, and even security devices. Typically, the network devices under attack are the endpoints, such as servers and desktop computers.

Question 4

What are the three primary vulnerabilities or weaknesses

Answer 4

technological, configuration, and security policy

Question 5

Describe technological vulnerabilities

Answer 5

TCP/IP Protocol Weakness
Hypertext Transfer Protocol (HTTP), File Transfer Protocol (FTP), and Internet Control Message Protocol (ICMP) are inherently insecure.
Simple Network Management Protocol (SNMP) and Simple Mail Transfer Protocol (SMTP) are related to the inherently insecure structure upon which TCP was designed.

Operating System Weakness
Each operating system has security problems what must be addressed.
UNIX, Linux, Mac OS, Mac OS X, Windows Server 2012, Windows 7, Windows 8
They are documented in the Computer Emergency Response Team (CERT) archives at http://www.cert.org

Network Equipment Weakness Various types of network equipment, such as routers, firewalls, and switches have security weaknesses that must be recognized and protected against. Their weaknesses include password protection, lack of authentication, routing protocols, and firewall holes.

Question 6

Describe configuration vulnerabilities

Answer 6

Unsecured user accounts User account information may be transmitted insecurely across the network, exposing usernames and passwords to threat actors.

System accounts with easily guessed passwords This common problem is the result of poorly created user passwords.

Misconfigured internet services Turning on JavaScript in web browsers enables attacks by way of JavaScript controlled by threat actors when accessing untrusted sites. Other potential sources of weaknesses include misconfigured terminal services, FTP, or web servers (e.g., Microsoft Internet Information Services (IIS), and Apache HTTP Server.

Unsecured default settings within products Many products have default settings that create or enable holes in security.

Misconfigured network equipment Misconfigurations of the equipment itself can cause significant security problems. For example, misconfigured access lists, routing protocols, or SNMP community strings can create or enable holes in security.

Question 7

Describe policy vulnerabilities

Answer 7

Lack of written security policy A security policy cannot be consistently applied or enforced if it is not written down.

Politics Political battles and turf wars can make it difficult to implement a consistent security policy.

Lack of authentication continuity Poorly chosen, easily cracked, or default passwords can allow unauthorized access to the network.

Logical access controls not applied Inadequate monitoring and auditing allow attacks and unauthorized use to continue, wasting company resources. This could result in legal action or termination against IT technicians, IT management, or even company leadership that allows these unsafe conditions to persist.

Software and hardware installation and changes do not follow policy Unauthorized changes to the network topology or installation of unapproved application create or enable holes in security.

Disaster recovery plan is nonexistent The lack of a disaster recovery plan allows chaos, panic, and confusion to occur when a natural disaster occurs or a threat actor attacks the enterprise

Question 8

Describe the four classes of physical threats

Answer 8

Hardware threats - This includes physical damage to servers, routers, switches, cabling plant, and workstations.
Environmental threats - This includes temperature extremes (too hot or too cold) or humidity extremes (too wet or too dry).
Electrical threats - This includes voltage spikes, insufficient supply voltage (brownouts), unconditioned power (noise), and total power loss.
Maintenance threats - This includes poor handling of key electrical components (electrostatic discharge), lack of critical spare parts, poor cabling, and poor labeling.

Question 9

What is malware

Answer 9

Malware is short for malicious software. It is code or software specifically designed to damage, disrupt, steal, or inflict “bad” or illegitimate action on data, hosts, or networks. Viruses, worms, and Trojan horses are types of malware.

Question 10

Describe viruses

Answer 10

A computer virus is a type of malware that propagates by inserting a copy of itself into, and becoming part of, another program. It spreads from one computer to another, leaving infections as it travels. Viruses can range in severity from causing mildly annoying effects, to damaging data or software and causing denial of service (DoS) conditions. Almost all viruses are attached to an executable file, which means the virus may exist on a system but will not be active or able to spread until a user runs or opens the malicious host file or program. When the host code is executed, the viral code is executed as well. Normally, the host program keeps functioning after the virus infects it. However, some viruses overwrite other programs with copies of themselves, which destroys the host program altogether. Viruses spread when the software or document they are attached to is transferred from one computer to another using the network, a disk, file sharing, or infected email attachments.

Question 11

Describe worms

Answer 11

Computer worms are similar to viruses in that they replicate functional copies of themselves and can cause the same type of damage. In contrast to viruses, which require the spreading of an infected host file, worms are standalone software and do not require a host program or human help to propagate. A worm does not need to attach to a program to infect a host and enter a computer through a vulnerability in the system. Worms take advantage of system features to travel through the network unaided.

Question 12

Describe Trojan Horse

Answer 12

A Trojan horse is another type of malware named after the wooden horse the Greeks used to infiltrate Troy. It is a harmful piece of software that looks legitimate. Users are typically tricked into loading and executing it on their systems. After it is activated, it can achieve any number of attacks on the host, from irritating the user (with excessive pop-up windows or changing the desktop) to damaging the host (deleting files, stealing data, or activating and spreading other malware, such as viruses). Trojan horses are also known to create back doors to give malicious users access to the system.

Unlike viruses and worms, Trojan horses do not reproduce by infecting other files. Trojan horses must spread through user interaction such as opening an email attachment or downloading and running a file from the internet.

Question 13

What are the categories of network attacks

Answer 13

Reconnaissance attacks - The discovery and mapping of systems, services, or vulnerabilities.
Access attacks - The unauthorized manipulation of data, system access, or user privileges.
Denial of service - The disabling or corruption of networks, systems, or services.

Question 14

Describe reconnaissance attacks

Answer 14

For reconnaissance attacks, external threat actors can use internet tools, such as the nslookup and whois utilities, to easily determine the IP address space assigned to a given corporation or entity. After the IP address space is determined, a threat actor can then ping the publicly available IP addresses to identify the addresses that are active. To help automate this step, a threat actor may use a ping sweep tool, such as fping or gping. This systematically pings all network addresses in a given range or subnet. This is similar to going through a section of a telephone book and calling each number to see who answers.

Question 15

Describe types of reconnaissance attack tools

Answer 15

Internet Queries
The threat actor is looking for initial information about a target. Various tools can be used, including Google search, the websites of organizations, whois, and more.

Ping Sweeps
The threat actor initiates a ping sweep to determine which IP addresses are active.

Port Scans
a threat actor performs a port scan on the discovered active IP addresses.

Question 16

What are the types of network attacks?

Answer 16

password attacks, trust exploitation, port redirection, and man-in-the middle

Question 17

Describe password attacks

Answer 17

Threat actors can implement password attacks using several different methods:

Brute-force attacks
Trojan horse attacks
Packet sniffers

Question 18

Describe Trust Exploitation

Answer 18

In a trust exploitation attack, a threat actor uses unauthorized privileges to gain access to a system, possibly compromising the target.

Question 19

Describe Port Redirection

Answer 19

In a port redirection attack, a threat actor uses a compromised system as a base for attacks against other targets

Question 20

Describe man in the middle

Answer 20

In a man-in-the-middle attack, the threat actor is positioned in between two legitimate entities in order to read or modify the data that passes between the two parties.

Question 21

Describe Denial of Service Attacks

Answer 21

DoS attacks are a major risk because they interrupt communication and cause significant loss of time and money. These attacks are relatively simple to conduct, even by an unskilled threat actor.
Eg sending so many pings such that a server can’t respond to anyone else

Question 22

Describe a Distributed Dos

Answer 22

A DDoS is similar to a DoS attack, but it originates from multiple, coordinated sources. For example, a threat actor builds a network of infected hosts, known as zombies. A network of zombies is called a botnet. The threat actor uses a command and control (CnC) program to instruct the botnet of zombies to carry out a DDoS attack.

Question 23

Describe the defense-in-depth approach

Answer 23

To mitigate network attacks, you must first secure devices including routers, switches, servers, and hosts. Most organizations employ a defense-in-depth approach (also known as a layered approach) to security. This requires a combination of networking devices and services working in tandem.

Question 24

List examples of some security devices and services

Answer 24

VPN- Arouter is used to provide secure VPN services with corporate sites and remote access support for remote users using secure encrypted tunnels

ASA Firewall- This dedicated device provides staateful firewall services. It ensures that internal traffic can go out and come back, but external traffic cannot initiate connections to inside hosts

IPS- An intrusion prevention system (IPS) monitors incoming and outgoing traffic looking for malware, network attack signatures and more. If it recognizes a threat, it can immediately stop it

ESA/WSA The email security appliance (ESA) filters spam and suspicious emails, The web security appliance (WSA) filters known and suspicious internet malware sites

AAA Server- This server contains a secure database of who is authorized to access and manage network devices. Network devices authenticate administrative users using this database

Question 25

Describe backups as a security feature

Answer 25

Backing up device configurations and data is one of the most effective ways of protecting against data loss. A data backup stores a copy of the information on a computer to removable backup media that can be kept in a safe place. Infrastructure devices should have backups of configuration files and IOS images on an FTP or similar file server. If the computer or a router hardware fails, the data or configuration can be restored using the backup copy.

Question 26

What are some considerations to be made when keeping backups

Answer 26

Frequency
Perform backups on a regular basis as identified in the security policy.
Full backups can be time-consuming, therefore perform monthly or weekly backups with frequent partial backups of changed files.

Validation
Always validate backups to ensure the integrity of the data and validate the file restoration procedures.

Storage
Backups should be transported to an approved offsite storage location on a daily, weekly, or monthly rotation, as required by the security policy.

Security
Backups should be protected using strong passwords. The password is required to restore the data.

Question 27

Describe upgrades, updates and patches

Answer 27

As new malware is released, enterprises need to keep current with the latest versions of antivirus software.

The most effective way to mitigate a worm attack is to download security updates from the operating system vendor and patch all vulnerable systems. Administering numerous systems involves the creation of a standard software image (operating system and accredited applications that are authorized for use on client systems) that is deployed on new or upgraded systems. However, security requirements change, and already deployed systems may need to have updated security patches installed.

One solution to the management of critical security patches is to make sure all end systems automatically download updates

Question 28

Describe Authentication, authorization, and accounting (AAA, or “triple A”) network security services

Answer 28

AAA is a way to control who is permitted to access a network (authenticate), what actions they perform while accessing the network (authorize), and making a record of what was done while they are there (accounting).

The concept of AAA is similar to the use of a credit card. The credit card identifies who can use it, how much that user can spend, and keeps account of what items the user spent money on

Question 29

Describe the use of firewalls

Answer 29

A firewall is one of the most effective security tools available for protecting users from external threats. A firewall protects computers and networks by preventing undesirable traffic from entering internal networks.

Network firewalls reside between two or more networks, control the traffic between them, and help prevent unauthorized access. A firewall could allow outside users controlled access to specific services. For example, servers accessible to outside users are usually located on a special network referred to as the demilitarized zone (DMZ), as shown in the figure. The DMZ enables a network administrator to apply specific policies for hosts connected to that network.

Question 30

Give different types of networks

Answer 30

Packet filtering - Prevents or allows access based on IP or MAC addresses
Application filtering - Prevents or allows access by specific application types based on port numbers
URL filtering - Prevents or allows access to websites based on specific URLs or keywords
Stateful packet inspection (SPI) - Incoming packets must be legitimate responses to requests from internal hosts. Unsolicited packets are blocked unless permitted specifically. SPI can also include the capability to recognize and filter out specific types of attacks, such as denial of service (DoS)

Question 31

Describe endpoint security

Answer 31

company must have well-documented policies in place and employees must be aware of these rules. Employees need to be trained on proper use of the network. Policies often include the use of antivirus software and host intrusion prevention. More comprehensive endpoint security solutions rely on network access control.

Question 32

Describe some simple steps that can be taken to ensure device security in most operating systems

Answer 32

Default usernames and passwords should be changed immediately.
Access to system resources should be restricted to only the individuals that are authorized to use those resources.
Any unnecessary services and applications should be turned off and uninstalled when possible.
Often, devices shipped from the manufacturer have been sitting in a warehouse for a period of time and do not have the most up-to-date patches installed. It is important to update any software and install any security patches prior to implementation.

Question 33

Give some password guidelines

Answer 33

Use a password length of at least eight characters, preferably 10 or more characters. A longer password is a more secure password.
Make passwords complex. Include a mix of uppercase and lowercase letters, numbers, symbols, and spaces, if allowed.
Avoid passwords based on repetition, common dictionary words, letter or number sequences, usernames, relative or pet names, biographical information, such as birthdates, ID numbers, ancestor names, or other easily identifiable pieces of information.
Deliberately misspell a password. For example, Smith = Smyth = 5mYth or Security = 5ecur1ty.
Change passwords often. If a password is unknowingly compromised, the window of opportunity for the threat actor to use the password is limited.
Do not write passwords down and leave them in obvious places such as on the desk or monitor.