Security+ Terminology Flashcards
3-leg perimeter
A type of DMZ where a firewall has three legs that connect to the LAN, the Internet, and the DMZ.
10 tape rotation
A backup rotation scheme in which ten backup tapes are used over the course of two weeks.
802.1X
An authentication technology used to connect devices to a LAN or WLAN. It is an example of port‐based network access control (NAC).
acceptable use
Often defined as a policy, acceptable use defines the rules that restrict how a computer, network, or other system may be used.
access control list (ACL)
A list of permissions attached to an object. ACLs specify what level of access a user, users, or groups have to an object. When dealing with firewalls, an ACL is a set of rules that applies to a list of network names, IP addresses, and port numbers.
access control model
Specifies methodologies by which admission to physical areas and, more importantly, computer systems, is managed and organized.
account expiration
The date when a user’s account they use to log on to the network expires.
accounting
The tracking of data, computer usage, and network resources. Often it means logging, auditing, and monitoring of the data and resources.
active interception
Normally refers to placing a computer between the sender and the receiver in an effort to capture and possibly modify information.
ad filtering
Ways of blocking and filtering out unwanted advertisements; pop‐up blockers and content filters are considered to be ad filtering methods.
Advanced Encryption Standard (AES)
An encryption standard used with WPA and WPA2. The
successor to DES/ 3DES and is another symmetric key encryption standard composed of three different
block ciphers: AES‐128, AES‐192, and AES‐256.
adware
Type of spyware that pops up advertisements based on what it has learned about the user.
algorithms
Well‐defined instructions that describe computations from their initial state to their final
state.
anomaly-based monitoring
Also known asstatistical anomaly‐based monitoring, establishes a performance baseline based on a set of normal network traffic evaluations.
AP isolation
Each client connected to the AP will not be able to communicate with each other, but they can each still access the Internet.
application black-listing
A method of disallowing one or more applications from use.
application firewall
A firewall that can control the traffic associated with specific applications. Works all the way up to the Application Layer of the OSI model.
application-level gateway (ALG)
Applies security mechanisms to specific applications, such as FTP and/or BitTorrent.
It supports address and port translation and checks whether the type of application traffic is allowed.
application white-listing
A method of restricting users to specific applications.
ARP poisoning
An attack that exploits Ethernet networks, and it may enable an attacker to sniff frames of information, modify that information, or stop it from getting to its intended destination.
asymmetric key algorithm
A type of cipher that uses a pair of different keys to encrypt and decrypt data.
attack vector
The path or means by which an attacker gains access to a computer.
audit trails
Records or logs that show the tracked actions of users, regardless of whether the users successfully completed the actions.
authentication
When a person’s identity is confirmed. Authentication is the verification of a person’s identity.
authorization
When a user is granted access to specific resources after authentication is complete.
availability
Data is obtainable regardless of how information is stored, accessed, or protected.
backdoors
Used in computer programs to bypass normal authentication and other security mechanisms in place.
back-to-back perimeter
A type of DMZ where the DMZ is located between the LAN and application‐ level gateway (ALG).
Applies security mechanisms to specific applications, such as FTP and/ or BitTorrent.
It supports address and port translation and checks whether the type of application traffic is allowed.
(Bonus: Blackout: When a total loss of power for a prolonged period occurs.)
blanket purchase agreement (BPA)
A service‐level agreement (SLA) that is reoccurring.
block cipher
A type of algorithm that encrypts a number of bits as individual units known as blocks.
bluejacking
The sending of unsolicited messages to Bluetooth‐enabled devices such as mobile phones and tablets.
bluesnarfing
The unauthorized access of information from a wireless device through a Bluetooth connection.
botnet
A group of compromised computers used to distribute malware across the Internet; the members are usually zombies.
broadcast storm
When there is an accumulation of broadcast and multicast packet traffic on the LAN coming from one or more network interfaces.
brownout
When the voltage drops to such an extent that it typically causes the lights to dim and causes computers to shut off.
brute-force attack
A password attack where every possible password is attempted.
buffer overflow
When a process stores data outside the memory that the developer intended to be used for storage. This could cause erratic behavior in the application, especially if the memory already had other data in it.
business impact analysis
The examination of critical versus noncritical functions, it is part of a business continuity plan (BCP).
butt set (or lineman’s handset)
A device that looks similar to a phone but has alligator clips that can connect to the various terminals used by phone equipment, enabling a person to listen in to a conversation.
CAM table (Content Addressable Memory)
A table that is in a switch’s memory that contains ports and their corresponding MAC addresses.
CAPTCHA
A type of challenge‐response mechanism used primarily in websites to tell whether or not the user is human.
Stands for Completely Automated Public Turing test to tell Computers and Humans Apart.
certificate authority (CA)
The entity (usually a server) that issues digital certificates to users.
certificate revocation list (CRL)
A list of certificates no longer valid or that have been revoked by the issuer.
certificates
Digitally signed electronic documents that bind a public key with a user identity.
chain of custody
Documents who had custody of evidence all the way up to litigation or a court trial (if necessary) and verifies that the evidence has not been modified.
Challenge Handshake Authentication Protocol (CHAP)
An authentication scheme used by the Point‐to‐Point Protocol (PPP) that is the standard for dial‐up connections.
change management
A structured way of changing the state of a computer system, network, or IT procedure.
chromatic dispersion
The refraction of light as in a rainbow. If light is refracted in such a manner on fiber‐optic cables, the signal cannot be read by the receiver.
cipher
hint: alogorithm
An algorithm that can perform encryption or decryption.
circuit-level gateway
Works at the Session Layer of the OSI model and applies security mechanisms when a TCP or UDP connection is established; acts as a go‐between for the Transport and Application Layers in TCP/ IP.
closed-circuit television (CCTV)
A video system (often used for surveillance) that makes use of traditional coaxial‐based video components, but is used privately, within a building or campus.
cloud computing
A way of offering on‐demand services that extend the capabilities of a person’s computer or an organization’s network.
cluster
Two or more servers that work with each other.
cold site
A site that has tables, chairs, bathrooms, and possibly some technical setup (for example, basic phone, data, and electric lines), but will require days if not weeks to set up properly.
Common Vulnerabilities and Exposures (CVE) ®
An online list of known vulnerabilities (and patches) to software, especially web servers. It is maintained by the MITRE Corporation.
computer security audits
Technical assessments made of applications, systems, or networks.
confidentiality
Preventing the disclosure of information to unauthorized persons.
content filters
Individual computer programs that block external files that use Java‐Script or images from loading into the browser.
cookies
Text files placed on the client computer that store information about it, which could include your computer’s browsing habits and credentials.
Tracking cookies are used by spyware to collect information about a web user’s activities.
Session cookies are used by attackers in an attempt to hijack a session.
cross-site request forgery (XSRF)
An attack that exploits the trust a website has in a user’s browser in an attempt to transmit unauthorized commands to the website.
cross-site scripting (XSS)
A type of vulnerability found in web applications used with session hijacking.
crosstalk
When a signal transmitted on one copper wire creates an undesired effect on another wire; the signal “bleeds” over, so to speak.
crypto-analysis attack
A password attack that uses a considerable set of precalculated encrypted passwords located in a lookup table.
cryptographic hash functions
Hash functions based on block ciphers.
cryptography
The practice and study of hiding information.
data emanation (or signal emanation)
The electromagnetic field generated by a network cable or network device, which can be manipulated to eavesdrop on conversations or to steal data.
Data Encryption Standard (DES)
An older type of block cipher selected by the United States federal government back in the 1970s as its encryption standard; due to its weak key, it is now considered deprecated.
data loss prevention (DLP)
Systems that are designed to protect data by way of content inspection.
They are meant to stop the leakage of confidential data, often concentrating on communications.
default account
An account installed by default on a device or within an operating system with a default set of user credentials that are usually insecure.
defense in depth
The building up and layering of security measures that protect data from inception, on through storage and network transfer, and lastly to final disposal.
demilitarized zone (DMZ)
A special area of the network (sometimes referred to as a subnetwork) that houses servers of host information accessed by clients or other networks on the Internet.
denial-of-service (DoS)
A broad term given to many different types of network attacks that attempt to make computer resources unavailable.
dictionary attack
A password attack that uses a prearranged list of likely words, trying each of them one at a time.
differential backup
Type of backup that backs up only the contents of a folder that have changed since the last full backup.
Diffie-Hellman
Key exchange Invented in the 1970s, it was the first practical method for establishing a shared secret key over an unprotected communications channel.
digital signature
A signature that authenticates a document through math, letting the recipient know that the document was created and sent by the actual sender and not someone else.
directory traversal
Also known as the ../ (dot dot slash) attack
A method of accessing unauthorized parent directories.
disaster recovery plan
A plan that details the policies and procedures concerning the recovery and/ or continuation of an organization’s technology infrastructure.
discretionary access control (DAC)
An access control policy generally determined by the owner.
distributed denial-of-service (DDoS)
An attack in which a group of compromised systems attack a single target, causing a DoS to occur at that host, usually using a botnet.
diversion theft
When a thief attempts to take responsibility for a shipment by diverting the delivery to a nearby location.
DNS poisoning
The modification of name resolution information that should be in a DNS server’s cache.
due care
The mitigation action that an organization takes to defend against the risks that have been uncovered during due diligence.
due process
The principle that an organization must respect and safeguard personnel’s rights.
dumpster diving
When a person literally scavenges for private information in garbage and recycling containers.
Easter egg
A platonic extra added to an OS or application as a sort of joke; the harmless cousin of the logic bomb.
due diligence
Ensuring that IT infrastructure risks are known and managed.
domain name kiting
The process of deleting a domain name during the five‐day grace period (known as the add grace period, or AGP) and immediately reregistering it for another five‐day period to keep a domain name indefinitely and for free.
disk duplexing
When each disk is connected to a separate controller.
eavesdropping
When a person uses direct observation to “listen” in to a conversation.
electromagnetic interference (EMI)
A disturbance that can affect electrical circuits, devices, and cables due to electromagnetic conduction or radiation.
elliptic curve cryptography (ECC)
A type of public key cryptography based on the structure of an elliptic curve.
encryption
The process of changing information using an algorithm (or cipher) into another form that is unreadable by others— unless they possess the key to that data.
ethical hacker
An expert at breaking into systems and can attack systems on behalf of the system’s owner and with the owner’s consent.
evil twin
A rogue wireless access point that uses the same SSID as a nearby legitimate access point.
explicit allow
When an administrator sets a rule that allows a specific type of traffic through a firewall, often within an ACL.
explicit deny
When an administrator sets a rule that denies a specific type of traffic access through a firewall, often within an ACL.
Extensible Authentication Protocol (EAP)
Not an authentication mechanism in itself but instead
defines message formats. 802.1X would be the authentication mechanism and defines how EAP is encapsulated within messages.
fail-open mode
When a switch broadcasts data on all ports the way a hub does.
failover clusters
Also known as high‐availability clusters, these are designed so that a secondary server can take over in the case that the primary one fails, with limited or no downtime.
false negative
When a system denies a user who actually should be allowed access to the system— for example, when an IDS/ IPS fails to block an attack, thinking it is legitimate traffic.
false positive
When a system authenticates a user who should not be allowed access to the system— for example, when an IDS/ IPS blocks legitimate traffic from passing on to the network.
false rejection
When a biometric system fails to recognize an authorized person and doesn’t allow that
person access.
Faraday cage
An enclosure formed by conducting material or by a mesh of such material; it blocks out external static electric fields and can stop emanations from cell phones and other devices within the cage from leaking out.
federated identity management (FIM)
When a user’s identity is shared across multiple identity management systems.
fire suppression
The process of controlling and/ or extinguishing fires to protect people and an organization’s data and equipment.
firewall
A part of a computer system or network designed to block unauthorized access while permitting authorized communications. It is a device or set of devices configured to permit or deny computer applications based on a set of rules and other criteria.
first responders
People who perform preliminary analysis of the incident data and determine whether the incident is an incident or just an event, and the criticality of the incident.
flood guard
Security feature implemented on some firewalls to protect against SYN floods and other flooding attacks. Also known as attack guards.
fork bomb
An attack that works by creating a large number of processes quickly to saturate the available processing space in the computer’s operating system. It is a type of wabbit.
Fraggle
A type of DoS similar to the Smurf attack, but the traffic sent is UDP echo traffic as opposed to ICMP echo traffic.
full backup
Type of backup where all the contents of a folder are backed up.
fuzz testing (fuzzing)
When random data is inputted into a computer program in an attempt to find vulnerabilities.
grandfather-father-son
A backup rotation scheme in which three sets of backup tapes must be defined— usually they are daily, weekly, and monthly, which correspond to son, father, and grandfather.
grayware
A general term used to describe applications that are behaving improperly but without serious consequences; often describes types of spyware. Group Policy is used in Microsoft environments to govern user and computer accounts through a set of rules.
hardening
The act of configuring an OS securely, updating it, creating rules and policies to help govern the system in a secure manner, and removing unnecessary applications and services.
hardware security module (HSM)
A physical device that deals with the encryption of authentication processes, digital signings and payment processes.
hash
A summary of a file or message. It is generated to verify the integrity of the file or message.
hash function
A mathematical procedure that converts a variable‐sized amount of data into a smaller block of data.
hoax
The attempt at deceiving people into believing something that is false.
honeynet
One or more computers, servers, or an area of a network, used to attract and trap potential attackers to counteract any attempts at unauthorized access of the network.
honeypot
Generally is a single computer but could also be a file, group of files, or an area of unused IP address space used to attract and trap potential attackers to counteract any attempts at unauthorized access of the network.
host-based intrusion detection system (HIDS)
A type of system loaded on an individual computer;
it analyzes and monitors what happens inside that computer— for example, if any changes have been
made to file integrity.
hot and cold aisles
The aisles in a server room or data center that circulate cold air into the systems and hot air out of them.
Usually, the systems and cabinets are supported by a raised floor.
hot site
A near duplicate of the original site of the organization, complete with phones, computers, networking devices, and full backups.
hotfix
Originally, a hotfix was defined as a single problem fixing patch to an individual OS or application that was installed live while the system was up and running, and without a reboot necessary.
However, this term has changed over time and varies from vendor to vendor.
HTTP proxy (web proxy)
Caches web pages from servers on the Internet for a set amount of time.
hypervisor
The portion of virtual machine software that allows multiple virtual operating systems (guests) to run at the same time on a single computer.
identification
When a person is in a state of being identified. It can also be described as something that identifies a person such as an ID card.
identity proofing
An initial validation of an identity.
incident management
The monitoring and detection of security events on a computer network and the execution of proper responses to those security events.
incident response
A set of procedures that an investigator follows when examining a computer security incident.
incremental backup
Type of backup that backs up only the contents of a folder that have changed since the last full backup or the last incremental backup.
information assurance
The practice of managing risks that are related to computer hardware and software systems.
information security
The act of protecting information from unauthorized access.
It usually includes an in‐depth plan on how to secure data, computers, and networks.
Infrastructure as a Service (IaaS)
A cloud computing service that offers computer networking, storage, load balancing, routing, and VM hosting.
input validation (data validation)
A process that ensures the correct usage of data.
integer overflow
When arithmetic operations attempt to create a numeric value that is too big for the available memory space.
integrity
This means that authorization is necessary before data can be modified.
Internet content filter
A filter that is usually applied as software at the Application Layer and can filter out various types of Internet activities such as websites accessed, e‐mail, instant messaging, and more.
It is used most often to disallow access to inappropriate web material.
Internet Protocol Security (IPsec)
A TCP/IP protocol that authenticates and encrypts IP packets, effectively securing communications between computers and devices using the protocol.
IP proxy
Secures a network by keeping machines behind it anonymous; it does this through the use of NAT.
IV attack
A type of related‐key attack, which is when an attacker observes the operation of a cipher using several different keys and finds a mathematical relationship between them, allowing the attacker to ultimately decipher data.
job rotation
When users are cycled through various assignments.
key
The essential piece of information that determines the output of a cipher.
key escrow
When certificate keys are held in case third parties, such as government or other organizations, need access to encrypted communications.
key recovery agent
Software that can be used to archive and restore keys if necessary.
key stretching
Takes a weak key, processes it, and outputs an enhanced and more powerful key, usually increasing key size to 128 bits.
LANMAN hash
The original hash used to store Windows passwords, known as LM hash, based off the DES algorithm.
Layer 2 Tunneling Protocol (L2TP)
A tunneling protocol used to connect virtual private networks. It does not include confidentiality or encryption on its own. It uses port 1701 and can be more secure than PPTP if used in conjunction with IPsec.
least privilege
When a user is given only the amount of privileges needed to do his job.
Lightweight Directory Access Protocol (LDAP)
An Application Layer protocol used for accessing and modifying directory service data.
load-balancing clusters
When multiple computers are connected in an attempt to share resources such as CPU, RAM, and hard disks.
locally shared objects (LSOs)
Also known as Flash cookies, these are files stored on users’ computers that allow websites to collect information about visitors.
Also referred to as “local shared objects.”
logic bomb
Code that has, in some way, been inserted into software; it is meant to initiate some type of malicious function when specific criteria are met.
MAC filtering
A method used to filter out which computers can access the wireless network; the WAP does this by consulting a list of MAC addresses that have been previously entered.
MAC flooding
An attack that sends numerous packets to a switch, each of which has a different source MAC address, in an attempt to use up the memory on the switch. If this is successful, the switch will change state to fail‐open mode.
mandatory access control (MAC)
An access control policy determined by a computer system, not by a user or owner, as it is in DAC.
mandatory vacations
When an organization requires that employees take a certain number of days of vacation consecutively.
man-in-the-browser (MITB)
Infects a vulnerable web browser and modifies online transactions. Similar to MITM.
man-in-the-middle (MITM)
A form of eavesdropping that intercepts all data between a client and a server, relaying that information back and forth.
mantrap
An area between two doorways, meant to hold people until they are identified and authenticated.
many-to-one mapping
When multiple certificates are mapped to a single recipient.
mean time between failures (MTBF)
Defines the average number of failures per million hours for a product in question.
memorandum of understanding (MoU)
A letter of intent between two entities (such as government agencies) concerning SLAs and BPAs.
Message‐Digest Algorithm 5 (MD5) A 128‐bit key hash used to provide integrity of files and messages.
mobile device management (MDM)
A centralized software solution that allows for the control and configuration of mobile devices.
multifactor authentication
When two or more types of authentication are used when dealing with user access control.
mutual authentication
When two computers (for example, a client and a server) verify each other’s identity.
network access control (NAC)
Sets the rules by which connections to a network are governed.
network address translation (NAT)
The process of changing an IP address while it is in transit across a router.
This is usually implemented so that one larger address space (private) can be remapped to another address space, or single IP address (public).
network intrusion detection system (NIDS)
A type of IDS that attempts to detect malicious network activities— for example, port scans and DoS attacks— by constantly monitoring network traffic.
network intrusion prevention system (NIPS)
Designed to inspect traffic, and based on its configuration or security policy, the system can remove, detain, or redirect malicious traffic.
Network Management System (NMS)
The software run on one or more servers that controls the monitoring of network‐attached devices and computers.
network mapping
The study of physical and logical connectivity of networks.
network perimeter
The border of a computer network, commonly secured by devices such as firewalls and NIDS/ NIPS solutions.
nonce
A random number issued by an authentication protocol that can only be used once.
non-promiscuous mode
When a network adapter captures only the packets that are addressed to it.
non-repudiation
The idea of ensuring that a person or group cannot refute the validity of your proof against them.
NTLM hash
Successor to the LM hash. A more advanced hash used to store Windows passwords, based off the RC4 algorithm.
NTLMv2 hash
Successor to the NTLM hash. Based off the MD5 hashing algorithm.
null session
When used by an attacker, a malicious connection to the Windows interprocess communications share (IPC $).
onboarding
When a new employee is added to an organization, and to its identity and access management system.
one-time pad
A cipher that encrypts plaintext with a secret random key that is the same length as the plain text.
one-to-one mapping
When an individual certificate is mapped to a single recipient.
Online Certificate Status Protocol (OCSP)
An alternative to using a certificate revocation list (CRL). It contains less information than a CRL does, and does not require encryption.
open mail relay
Also known as an SMTP open relay, enables anyone on the Internet to send e‐mail through an SMTP server.
Open Vulnerability and Assessment Language (OVAL)
A standard and a programming language designed to standardize the transfer of secure public information across networks and the Internet utilizing any security tools and services available.
packet filtering
In the context of firewalls, inspects each packet passing through the firewall and accepts or rejects it based on rules.
Two types of packet filtering include stateless packet filters and stateful packet inspection (SPI).
password cracker
Software tool used to recover passwords from hosts or to discover weak passwords.
patch
An update to a system. Patches generally carry the connotation of a small fix in the mind of the user or system administrator, so larger patches often are referred to as software updates, service packs, or something similar.
patch management
The planning, testing, implementing, and auditing of patches.
Kerberos
An authentication protocol that enables computers to prove their identity to each other in a secure manner.
implicit deny
Denies all traffic to a resource unless the users generating that traffic are specifically granted access to the resource.
For example, when a device denies all traffic unless a rule is made to open the port associated with the type of traffic desired to be let through.
penetration testing
A method of evaluating the security of a system by simulating one or more attacks on that system.
permanent DoS (PDoS) attack
Generally consists of an attacker exploiting security flaws in routers and other networking hardware by flashing the firmware of the device and replacing it with a modified image.
permissions
Control which file system resources a person can access on the network.
personal firewall
An application that protects an individual computer from unwanted Internet traffic; it does so by way of a set of rules and policies.
personally identifiable information (PII)
Information used to uniquely identify, contact, or locate a person.
pharming
When an attacker redirects one website’s traffic to another bogus and possibly malicious website by modifying a DNS server or hosts file.
phishing
The criminally fraudulent process of attempting to acquire sensitive information such as usernames, passwords, and credit card details by masquerading as a trustworthy entity in an electronic communication.
piggybacking
When an unauthorized person tags along with an authorized person to gain entry to a restricted area.
ping flood
When an attacker attempts to send many ICMP echo request packets (pings) to a host in an attempt to use up all available bandwidth. Also known as an ICMP flood attack.
Ping of Death (POD)
A type of DoS that sends an oversized and/ or malformed packet to another computer.
Platform as a Service (PaaS)
A cloud computing service that provides various software solutions to organizations, especially the ability to develop applications without the cost or administration of a physical platform.
policy
Rules or guidelines used to guide decisions and achieve outcomes. They can be written or configured on a computer.
pop-up blocker
An application or add‐on to a web browser that blocks pop‐up windows that usually contain advertisements.
port address translation (PAT)
Like NAT, but it translates both IP addresses and port numbers.
port scanner
Software used to decipher which ports are open on a host.
pre-action sprinkler system
Similar to a dry pipe system, but there are requirements for it to be set off such as heat or smoke.
pretexting
When a person invents a scenario, or pretext, in the hope of persuading a victim to divulge information.
Pretty Good Privacy (PGP)
An encryption program used primarily for signing, encrypting, and decrypting e‐mails in an attempt to increase the security of e‐mail communications.
private key
A type of key that is known only to a specific user or users who keep the key a secret.
privilege escalation
The act of exploiting a bug or design flaw in a software or firmware application to gain access to resources that normally would’ve been protected from an application or user.
promiscuous mode
In a network adapter, this passes all traffic to the CPU, not just the frames addressed to it.
When the network adapter captures all packets that it has access to regardless of the destination for those packets.
protected distribution system
Security system implemented to protect unencrypted data transfer over wired networks.
Protected Extensible Authentication Protocol (PEAP)
Protocol used to encapsulate EAP packets within encrypted and authenticated tunnels.
protocol analyzer
Software tool used to capture and analyze packets.
proxy server
Acts as an intermediary between clients, usually located on a LAN, and the servers that they want to access, usually located on the Internet.
public key
A type of key that is known to all parties involved in encrypted transactions within a given group.
public key cryptography
Uses asymmetric keys alone or in addition to symmetric keys. The asymmetric key algorithm creates a secret private key and a published public key.
public key infrastructure (PKI)
An entire system of hardware and software, policies and procedures, and people, used to create, distribute, manage, store, and revoke digital certificates.
qualitative risk assessment
An assessment that assigns numeric values to the probability of a risk and the impact it can have on the system or network.
quantitative risk assessment
An assessment that measures risk by using exact monetary values.
radio frequency interference (RFI)
Interference that can come from AM/ FM transmissions and cell towers.
RAID 1 Mirroring.
Data is copied to two identical disks. If one disk fails, the other continues to operate.
RAID 5 Striping with parity.
Data striped across multiple disks; fault‐tolerant parity data is also written to each disk.
rainbow table
In password cracking, a set of precalculated encrypted passwords located in a lookup table.
ransomware
A type of malware that restricts access to a computer system, and demands a ransom be paid.
recovery point objective (RPO)
In business impact analysis, the acceptable latency of data.
recovery time objective (RTO)
In business impact analysis, the acceptable amount of time to restore a function.
redundant ISP
Secondary connections to another ISP; for example, a backup T‐1 line.
redundant power supply
An enclosure that contains two complete power supplies, the second of which turns on when the first fails.
registration authority (RA)
Used to verify requests for certificates.
Remote Access Service (RAS)
A networking service that allows incoming connections from remote dial‐in clients. It is also used with VPNs.
Remote Authentication Dial-In User Service (RADIUS)
Used to provide centralized administration of dial‐up, VPN, and wireless authentication.
remote code execution (RCE)
When an attacker acquires control of a remote computer through a code vulnerability.
Also known as arbitrary code execution.
Attackers often use a web browser’s URL field or a tool such as Netcat to accomplish this.
replay attack
An attack in which valid data transmission is maliciously or fraudulently repeated or delayed.
residual risk
The risk that is left over after a security plan and a disaster recovery plan have been implemented.
risk
The possibility of a malicious attack or other threat causing damage or downtime to a computer system.
risk acceptance
The amount of risk an organization is willing to accept. Also known as risk retention.
risk assessment
The attempt to determine the amount of threats or hazards that could possibly occur in a given amount of time to your computers and networks.
risk avoidance
When an organization avoid risk because the risk factor is too great.
risk management
The identification, assessment, and prioritization of risks, and the mitigation and monitoring of those risks.
risk mitigation
When a risk is reduced or eliminated altogether.
risk reduction
When an organization mitigates risk to an acceptable level.
risk transference
The transfer or outsourcing of risk to a third party. Also known as risk sharing.
role-based access control (RBAC)
An access model that works with sets of permissions, instead of individual permissions that are label‐based. So roles are created for various job functions in an organization.
rootkit
A type of software designed to gain administrator‐level control over a computer system without being detected.
RSA
A public key cryptography algorithm created by Rivest, Shamir, Adleman. It is commonly used in e‐ commerce.
sag
An unexpected decrease in the amount of voltage provided.
salting
The randomization of the hashing process to defend against crypto-analysis password attacks and rainbow tables.
sandbox
When a web script runs in its own environment for the express purpose of not interfering with other processes, possibly for testing.
secure code review
An in‐depth code inspection procedure.
secure coding concepts
The best practices used during the life cycle of software development.
Secure Hash Algorithm (SHA)
A group of hash functions designed by the NSA and published by the NIST, widely used in government. The most common currently is SHA‐1.
Secure Shell (SSH)
A protocol that can create a secure channel between two computers or network devices.
Secure Sockets Layer (SSL)
A cryptographic protocol that provides secure Internet communications such as web browsing, instant messaging, e‐mail, and VoIP.
security log files
Files that log activity of users.
They show who did what and when, plus whether they succeeded or failed in their attempt.
security posture
The risk level to which a system, or other technology element, is exposed.
security posture assessment (SPA)
An assessment that uses baseline reporting and other analyses to discover vulnerabilities and weaknesses in systems and networks.
security template
Groups of policies that can be loaded in one procedure.
security tokens
Physical devices given to authorized users to help with authentication. These devices might be attached to a keychain or are part of a card system.
separation of duties (SoD)
This is when more than one person is required to complete a particular task or operation.
service-level agreement (SLA)
Part of a service contract where the level of service is formally defined.
service pack (SP)
A group of updates, bug fixes, updated drivers, and security fixes that is installed from one downloadable package or from one disc.
service set identifier (SSID)
The name of a wireless access point (or network) to which network clients will connect; it is broadcast through the air.
shoulder surfing
When a person uses direct observation to find out a target’s password, PIN, or other such authentication information.
signature-based monitoring
Frames and packets of network traffic are analyzed for predetermined attack patterns. These attack patterns are known as signatures.
Simple Network Management Protocol (SNMP)
A TCP/ IP protocol that monitors network‐attached devices and computers. It’s usually incorporated as part of a network management system.
single point of failure
An element, object, or part of a system that, if it fails, will cause the whole system to fail.
single sign-on (SSO)
When a user can log in once but gain access to multiple systems without being asked to log in again.
Smurf attack
A type of DoS that sends large amounts of ICMP echoes, broadcasting the ICMP echo requests to every computer on its network or subnetwork. The header of the ICMP echo requests will have a spoofed IP address. That IP address is the target of the Smurf attack. Every computer that replies to the ICMP echo requests will do so to the spoofed IP.
SNMP agent
Software deployed by the network management system that is loaded on managed devices. The software redirects the information that the NMS needs to monitor the remote managed devices.
Software as a Service (SaaS)
A cloud computing service where users access applications over the Internet that are provided by a third party.
spam
The abuse of electronic messaging systems such as e‐mail and broadcast media
(Bonus)
Spear phishing - A type of phishing attack that targets particular individuals.
special hazard protection system
A clean agent sprinkler system such as FM‐200 used in server rooms.
spike
A short transient in voltage that can be due to a short circuit, tripped circuit breaker, power outage, or lightning strike.
spim
The abuse of instant messaging systems, a derivative of spam.
spoofing
When an attacker masquerades as another person by falsifying information.
spyware
A type of malicious software either downloaded unwittingly from a website or installed along with some other third‐party software.
standby generator
Systems that turn on automatically within seconds of a power outage.
stateful packet inspection (SPI)
Type of packet inspection that keeps track of network connections by examining the header in each packet.
static NAT
When a single private IP address translates to a single public IP address. This is also called one‐to‐one mapping.
steganography
The science (and art) of writing hidden messages; it is a form of security through obscurity.
storage segmentation
A clear separation of organizational and personal information, applications, and other content.
stream cipher
A type of algorithm that encrypts each byte in a message one at a time.
supervisory control and data acquisition (SCADA)
System of hardware and software that controls and monitors industrial systems such as HVAC.
surge
Means that there is an unexpected increase in the amount of voltage provided.
symmetric key algorithm
A class of cipher that uses identical or closely related keys for encryption and decryption.
SYN flood
A type of DoS where an attacker sends a large amount of SYN request packets to a server in an attempt to deny service.
Systems Development Life Cycle (SDLC)
The process of creating systems and applications, and the methodologies used to do so.
tailgating
A type of piggybacking where an unauthorized person follows an authorized person into a secure area, without the authorized person’s consent.
TCP reset attack
Sets the reset flag in a TCP header to 1, telling the respective computer to kill the TCP session immediately.
TCP/ IP hijacking
When a hacker takes over a TCP session between two computers without the need of a cookie or any other type of host access.
teardrop attack
A type of DoS that sends mangled IP fragments with overlapping and oversized
payloads to the target machine.
TEMPEST
Refers to the investigations of conducted emissions from electrical and mechanical devices, which could be compromising to an organization.
Temporal Key Integrity Protocol (TKIP)
An algorithm used to secure wireless computer networks; meant as a replacement for WEP.
Terminal Access Controller Access-Control System Plus (TACACS +)
A remote authentication protocol similar to RADIUS used in Cisco networks.
(Bonus)
Threat Modeling
A way of prioritizing threats to an application.
threat vector
The method a threat uses to gain access to a target computer.
tickets
Part of the authentication process used by Kerberos.
time bomb
A Trojan set off on a certain date.
time of day restriction
When a user’s logon hours are configured to restrict access to the network during certain times of the day and week.
Towers of Hanoi
A backup rotation scheme based on the mathematics of the Towers of Hanoi puzzle.
Uses three backup sets. For example, the first tape is used every second day, the second tape is used every fourth day, and the third tape is used every eighth day.
Transport Layer Security (TLS)
The successor to SSL. Provides secure Internet communications. This is shown in a browser as HTTPS.
Triple DES (3DES)
Similar to DES but applies the cipher algorithm three times to each cipher block.
Trojan horse
An application that appears to perform desired functions but is actually performing
malicious functions behind the scenes.
Trusted Computer System Evaluation Criteria (TCSEC)
A DoD standard that sets basic requirements for assessing the effectiveness of computer security access policies. Also known as The Orange Book.
Trusted Operating System (TOS)
A system that adheres to criteria for multilevel security and meets government regulations.
typosquatting (URL hijacking)
A method used by attackers that takes advantage of user typos when accessing websites. Instead of the expected website, the user ends up at a website with a similar name but often malicious content.
UDP flood attack
A similar attack to the Fraggle. It uses the connectionless User Datagram Protocol. It is enticing to attackers because it does not require a synchronization process.
uninterruptible power supply (UPS)
Takes the functionality of a surge suppressor and combines that with a battery backup, protecting computers not only from surges and spikes, but also from sags, brownouts, and blackouts.
User Account Control (UAC)
A Security component of Windows that keeps every user (besides the actual Administrator account) in standard user mode instead of as an administrator with full administrative rights— even if they are a member of the administrators group.
vampire tap
A device used to add computers to a 10BASE5 network. It pierces the copper conductor of a coaxial cable and can also be used for malicious purposes.
virtual machine (VM)
Created by virtual software; VMs are images of operating systems or individual applications.
virtual private network (VPN)
A connection between two or more computers or devices that are not on the same private network.
virtualization
The creation of a virtual entity, as opposed to a true or actual entity.
virus
Code that runs on a computer without the user’s knowledge; it infects the computer when the code is accessed and executed.
vishing
A type of phishing attack that makes use of telephones and VoIP.
VLAN hopping
The act of gaining access to traffic on other VLANs that would not normally be accessible by jumping from one VLAN to another.
VPN concentrator
A hardware appliance that allows hundreds of users to connect to the network from remote locations via a VPN.
vulnerability
Weaknesses in your computer network design and individual host configuration.
vulnerability assessment
Baselining of the network to assess the current security state of computers, servers, network devices, and the entire network in general.
vulnerability management
The practice of finding and mitigating software vulnerabilities in computers and networks.
vulnerability scanning
The act of scanning for weaknesses and susceptibility in the network and on individual systems.
war-chalking
The act of physically drawing symbols in public places that denote open, closed, or
protected wireless networks.
war-dialing
The act of scanning telephone numbers by dialing them one at a time and adding them to a list, in an attempt to gain access to computer networks.
war-driving
The act of searching for wireless networks by a person in a vehicle through the use of a device with a wireless antenna, often a particularly strong antenna.
warm site
A site that has computers, phones, and servers, but they might require some configuration before users can start working on them.
watering hole attack
An attacker profiles which websites a user accesses and later infects those sites to redirect the user to other websites.
web of trust
A decentralized model used for sharing certificates without the need for a centralized CA.
web security gateway
An intermediary that can scan for viruses and filter Internet content.
wet pipe sprinkler system
Consists of a pressurized water supply system that can deliver a high quantity of water to an entire building via a piping distribution system.
whaling
A phishing attack that targets senior executives.
white-box testing
A method of testing applications or systems where the tester is given access to the internal workings of the system.
white hat
A type of hacker that is contracted to break into a company’s system.
Wi-Fi Protected Setup (WPS)
A security protocol created by the Wi‐Fi Alliance to secure wireless computer networks; more secure than WEP.
Wired Equivalent Privacy (WEP)
A deprecated wireless network security standard, less secure than WPA.
wiretapping
Tapping into a network cable in an attempt to eavesdrop on a conversation or steal data.
worm
Code that runs on a computer without the user’s knowledge; a worm self‐replicates, whereas a virus does not.
X. 509
A common PKI standard developed by the ITU‐T that incorporates the single sign‐on authentication method.
zero day attack
An attack that is executed on a vulnerability in software before that vulnerability is known to the creator of the software.
zombie
An individual compromised computer in a botnet.
S/ MIME
An IETF standard that provides cryptographic security for electronic messaging such as e‐mail.
Point-to-Point Tunneling Protocol (PPTP)
A tunneling protocol used to support VPNs. Generally includes security mechanisms, and no additional software or protocols need to be loaded. A VPN device or server must have inbound port 1723 open to enable incoming PPTP connections.
