Information security

Information security threats come in many different forms.[35][36] Some of the most common threats today are software attacks, theft of intellectual property, theft of identity, theft of equipment or information, sabotage, and information extortion.[37][38] Viruses,[39] worms, phishing attacks, and Trojan horses are a few common examples of software attacks. The theft of intellectual property has also been an extensive issue for many businesses in the information technology (IT) field.[40] Identity theft is the attempt to act as someone else usually to obtain that person's personal information or to take advantage of their access to vital information through social engineering.[41][42] Theft of equipment or information is becoming more prevalent today due to the fact that most devices today are mobile,[43] are prone to theft and have also become far more desirable as the amount of data capacity increases. Sabotage usually consists of the destruction of an organization's website in an attempt to cause loss of confidence on the part of its customers.[44] Information extortion consists of theft of a company's property or information as an attempt to receive a payment in exchange for returning the information or property back to its owner, as with ransomware.[45] There are many ways to help protect yourself from some of these attacks but one of the most functional precautions is conduct periodical user awareness.[46] The number one threat to any organisation are users or internal employees, they are also called insider threats.[47]

Governments, military, corporations, financial institutions, hospitals, non-profit organisations, and private businesses amass a great deal of confidential information about their employees, customers, products, research, and financial status.[48] Should confidential information about a business's customers or finances or new product line fall into the hands of a competitor or a black hat hacker, a business and its customers could suffer widespread, irreparable financial loss, as well as damage to the company's reputation.[49] From a business perspective, information security must be balanced against cost; the Gordon-Loeb Model provides a mathematical economic approach for addressing this concern.[50]

For the individual, information security has a significant effect on privacy, which is viewed very differently in various cultures.[51]

Possible responses to a security threat or risk are:[52]

• reduce/mitigate – implement safeguards and countermeasures to eliminate vulnerabilities or block threats
• assign/transfer – place the cost of the threat onto another entity or organization such as purchasing insurance or outsourcing
• accept – evaluate if the cost of the countermeasure outweighs the possible cost of loss due to the threat[53]

Poster promoting information security by the Russian Ministry of Defence

The "CIA" triad of confidentiality, integrity, and availability is at the heart of information security.[79] (The members of the classic InfoSec triad—confidentiality, integrity, and availability—are interchangeably referred to in the literature as security attributes, properties, security goals, fundamental aspects, information criteria, critical information characteristics and basic building blocks.)[80] However, debate continues about whether or not this triad is sufficient to address rapidly changing technology and business requirements, with recommendations to consider expanding on the intersections between availability and confidentiality, as well as the relationship between security and privacy.[24] Other principles such as "accountability" have sometimes been proposed; it has been pointed out that issues such as non-repudiation do not fit well within the three core concepts.[81]

The triad seems to have first been mentioned in a NIST publication in 1977.[82]

In 1992 and revised in 2002, the OECD's Guidelines for the Security of Information Systems and Networks[83] proposed the nine generally accepted principles: awareness, responsibility, response, ethics, democracy, risk assessment, security design and implementation, security management, and reassessment.[84] Building upon those, in 2004 the NIST's Engineering Principles for Information Technology Security[81] proposed 33 principles. From each of these derived guidelines and practices.

In 1998, Donn Parker proposed an alternative model for the classic "CIA" triad that he called the six atomic elements of information. The elements are confidentiality, possession, integrity, authenticity, availability, and utility. The merits of the Parkerian Hexad are a subject of debate amongst security professionals.[85]

In 2011, The Open Group published the information security management standard O-ISM3.[86] This standard proposed an operational definition of the key concepts of security, with elements called "security objectives", related to access control (9), availability (3), data quality (1), compliance, and technical (4). In 2009, DoD Software Protection Initiative Archived 2016-09-25 at the Wayback Machine released the Three Tenets of Cybersecurity Archived 2020-05-10 at the Wayback Machine which are System Susceptibility, Access to the Flaw, and Capability to Exploit the Flaw.[87][88][89] Neither of these models are widely adopted.

In information security, confidentiality "is the property, that information is not made available or disclosed to unauthorized individuals, entities, or processes."[90] While similar to "privacy," the two words are not interchangeable. Rather, confidentiality is a component of privacy that implements to protect our data from unauthorized viewers.[91] Examples of confidentiality of electronic data being compromised include laptop theft, password theft, or sensitive emails being sent to the incorrect individuals.[92]

In IT security, data integrity means maintaining and assuring the accuracy and completeness of data over its entire lifecycle.[93] This means that data cannot be modified in an unauthorized or undetected manner.[94] This is not the same thing as referential integrity in databases, although it can be viewed as a special case of consistency as understood in the classic ACID model of transaction processing.[95] Information security systems typically incorporate controls to ensure their own integrity, in particular protecting the kernel or core functions against both deliberate and accidental threats.[96] Multi-purpose and multi-user computer systems aim to compartmentalize the data and processing such that no user or process can adversely impact another: the controls may not succeed however, as we see in incidents such as malware infections, hacks, data theft, fraud, and privacy breaches.[97]

More broadly, integrity is an information security principle that involves human/social, process, and commercial integrity, as well as data integrity. As such it touches on aspects such as credibility, consistency, truthfulness, completeness, accuracy, timeliness, and assurance.[98]

For any information system to serve its purpose, the information must be available when it is needed.[99] This means the computing systems used to store and process the information, the security controls used to protect it, and the communication channels used to access it must be functioning correctly.[100] High availability systems aim to remain available at all times, preventing service disruptions due to power outages, hardware failures, and system upgrades.[101] Ensuring availability also involves preventing denial-of-service attacks, such as a flood of incoming messages to the target system, essentially forcing it to shut down.[102]

In the realm of information security, availability can often be viewed as one of the most important parts of a successful information security program. Ultimately end-users need to be able to perform job functions; by ensuring availability an organization is able to perform to the standards that an organization's stakeholders expect.[103] This can involve topics such as proxy configurations, outside web access, the ability to access shared drives and the ability to send emails.[104] Executives oftentimes do not understand the technical side of information security and look at availability as an easy fix, but this often requires collaboration from many different organizational teams, such as network operations, development operations, incident response, and policy/change management.[105] A successful information security team involves many different key roles to mesh and align for the "CIA" triad to be provided effectively.[106]

In law, non-repudiation implies one's intention to fulfill their obligations to a contract. It also implies that one party of a transaction cannot deny having received a transaction, nor can the other party deny having sent a transaction.[107]

It is important to note that while technology such as cryptographic systems can assist in non-repudiation efforts, the concept is at its core a legal concept transcending the realm of technology.[108] It is not, for instance, sufficient to show that the message matches a digital signature signed with the sender's private key, and thus only the sender could have sent the message, and nobody else could have altered it in transit (data integrity).[109] The alleged sender could in return demonstrate that the digital signature algorithm is vulnerable or flawed, or allege or prove that his signing key has been compromised.[110] The fault for these violations may or may not lie with the sender, and such assertions may or may not relieve the sender of liability, but the assertion would invalidate the claim that the signature necessarily proves authenticity and integrity. As such, the sender may repudiate the message (because authenticity and integrity are pre-requisites for non-repudiation).[111]

Selecting and implementing proper security controls will initially help an organization bring down risk to acceptable levels.[137] Control selection should follow and should be based on the risk assessment.[138] Controls can vary in nature, but fundamentally they are ways of protecting the confidentiality, integrity or availability of information. ISO/IEC 27001 has defined controls in different areas.[139] Organizations can implement additional controls according to requirement of the organization.[140] ISO/IEC 27002 offers a guideline for organizational information security standards.[141]

Administrative controls (also called procedural controls) consist of approved written policies, procedures, standards, and guidelines. Administrative controls form the framework for running the business and managing people.[142] They inform people on how the business is to be run and how day-to-day operations are to be conducted. Laws and regulations created by government bodies are also a type of administrative control because they inform the business.[143] Some industry sectors have policies, procedures, standards, and guidelines that must be followed – the Payment Card Industry Data Security Standard[144] (PCI DSS) required by Visa and MasterCard is such an example. Other examples of administrative controls include the corporate security policy, password policy, hiring policies, and disciplinary policies.[145]

Administrative controls form the basis for the selection and implementation of logical and physical controls. Logical and physical controls are manifestations of administrative controls, which are of paramount importance.[142]

Logical controls (also called technical controls) use software and data to monitor and control access to information and computing systems. Passwords, network and host-based firewalls, network intrusion detection systems, access control lists, and data encryption are examples of logical controls.[146]

An important logical control that is frequently overlooked is the principle of least privilege, which requires that an individual, program or system process not be granted any more access privileges than are necessary to perform the task.[147] A blatant example of the failure to adhere to the principle of least privilege is logging into Windows as user Administrator to read email and surf the web. Violations of this principle can also occur when an individual collects additional access privileges over time.[148] This happens when employees' job duties change, employees are promoted to a new position, or employees are transferred to another department.[149] The access privileges required by their new duties are frequently added onto their already existing access privileges, which may no longer be necessary or appropriate.[150]

Physical controls monitor and control the environment of the work place and computing facilities.[151] They also monitor and control access to and from such facilities and include doors, locks, heating and air conditioning, smoke and fire alarms, fire suppression systems, cameras, barricades, fencing, security guards, cable locks, etc. Separating the network and workplace into functional areas are also physical controls.[152]

An important physical control that is frequently overlooked is separation of duties, which ensures that an individual can not complete a critical task by himself.[153] For example, an employee who submits a request for reimbursement should not also be able to authorize payment or print the check.[154] An applications programmer should not also be the server administrator or the database administrator; these roles and responsibilities must be separated from one another.[155]

The onion model of defense in depth

Information security must protect information throughout its lifespan, from the initial creation of the information on through to the final disposal of the information.[156] The information must be protected while in motion and while at rest. During its lifetime, information may pass through many different information processing systems and through many different parts of information processing systems.[157] There are many different ways the information and information systems can be threatened. To fully protect the information during its lifetime, each component of the information processing system must have its own protection mechanisms.[158] The building up, layering on, and overlapping of security measures is called "defense in depth."[159] In contrast to a metal chain, which is famously only as strong as its weakest link, the defense in depth strategy aims at a structure where, should one defensive measure fail, other measures will continue to provide protection.[160]

Recall the earlier discussion about administrative controls, logical controls, and physical controls. The three types of controls can be used to form the basis upon which to build a defense in depth strategy.[142] With this approach, defense in depth can be conceptualized as three distinct layers or planes laid one on top of the other.[161] Additional insight into defense in depth can be gained by thinking of it as forming the layers of an onion, with data at the core of the onion, people the next outer layer of the onion, and network security, host-based security, and application security forming the outermost layers of the onion.[162] Both perspectives are equally valid, and each provides valuable insight into the implementation of a good defense in depth strategy.[163]

An important aspect of information security and risk management is recognizing the value of information and defining appropriate procedures and protection requirements for the information.[164] Not all information is equal and so not all information requires the same degree of protection.[165] This requires information to be assigned a security classification.[166] The first step in information classification is to identify a member of senior management as the owner of the particular information to be classified. Next, develop a classification policy.[167] The policy should describe the different classification labels, define the criteria for information to be assigned a particular label, and list the required security controls for each classification.[168]

Some factors that influence which classification information should be assigned include how much value that information has to the organization, how old the information is and whether or not the information has become obsolete.[169] Laws and other regulatory requirements are also important considerations when classifying information.[170] The Information Systems Audit and Control Association (ISACA) and its Business Model for Information Security also serves as a tool for security professionals to examine security from a systems perspective, creating an environment where security can be managed holistically, allowing actual risks to be addressed.[171]

The type of information security classification labels selected and used will depend on the nature of the organization, with examples being:[168]

• In the business sector, labels such as: Public, Sensitive, Private, Confidential.
• In the government sector, labels such as: Unclassified, Unofficial, Protected, Confidential, Secret, Top Secret, and their non-English equivalents.[172]
• In cross-sectoral formations, the Traffic Light Protocol, which consists of: White, Green, Amber, and Red.
• In the personal sector, one label such as Financial. This includes activities related to managing money, such as online banking.[173]

All employees in the organization, as well as business partners, must be trained on the classification schema and understand the required security controls and handling procedures for each classification.[174] The classification of a particular information asset that has been assigned should be reviewed periodically to ensure the classification is still appropriate for the information and to ensure the security controls required by the classification are in place and are followed in their right procedures.[175]

Access to protected information must be restricted to people who are authorized to access the information.[176] The computer programs, and in many cases the computers that process the information, must also be authorized.[177] This requires that mechanisms be in place to control the access to protected information.[177] The sophistication of the access control mechanisms should be in parity with the value of the information being protected; the more sensitive or valuable the information the stronger the control mechanisms need to be.[178] The foundation on which access control mechanisms are built start with identification and authentication.[179]

Access control is generally considered in three steps: identification, authentication, and authorization.[180][92]

Identification is an assertion of who someone is or what something is. If a person makes the statement "Hello, my name is John Doe" they are making a claim of who they are.[181] However, their claim may or may not be true. Before John Doe can be granted access to protected information it will be necessary to verify that the person claiming to be John Doe really is John Doe.[182] Typically the claim is in the form of a username. By entering that username you are claiming "I am the person the username belongs to".[183]

Authentication is the act of verifying a claim of identity. When John Doe goes into a bank to make a withdrawal, he tells the bank teller he is John Doe, a claim of identity.[184] The bank teller asks to see a photo ID, so he hands the teller his driver's license.[185] The bank teller checks the license to make sure it has John Doe printed on it and compares the photograph on the license against the person claiming to be John Doe.[186] If the photo and name match the person, then the teller has authenticated that John Doe is who he claimed to be. Similarly, by entering the correct password, the user is providing evidence that he/she is the person the username belongs to.[187]

There are three different types of information that can be used for authentication:[188][189]

• Something you know: things such as a PIN, a password, or your mother's maiden name[190][191]
• Something you have: a driver's license or a magnetic swipe card[192][193]
• Something you are: biometrics, including palm prints, fingerprints, voice prints, and retina (eye) scans[194]

Strong authentication requires providing more than one type of authentication information (two-factor authentication).[195] The username is the most common form of identification on computer systems today and the password is the most common form of authentication.[196] Usernames and passwords have served their purpose, but they are increasingly inadequate.[197] Usernames and passwords are slowly being replaced or supplemented with more sophisticated authentication mechanisms such as Time-based One-time Password algorithms.[198]

After a person, program or computer has successfully been identified and authenticated then it must be determined what informational resources they are permitted to access and what actions they will be allowed to perform (run, view, create, delete, or change).[199] This is called authorization. Authorization to access information and other computing services begins with administrative policies and procedures.[200] The policies prescribe what information and computing services can be accessed, by whom, and under what conditions. The access control mechanisms are then configured to enforce these policies.[201] Different computing systems are equipped with different kinds of access control mechanisms. Some may even offer a choice of different access control mechanisms.[202] The access control mechanism a system offers will be based upon one of three approaches to access control, or it may be derived from a combination of the three approaches.[92]

The non-discretionary approach consolidates all access control under a centralized administration.[203] The access to information and other resources is usually based on the individuals function (role) in the organization or the tasks the individual must perform.[204][205] The discretionary approach gives the creator or owner of the information resource the ability to control access to those resources.[203] In the mandatory access control approach, access is granted or denied basing upon the security classification assigned to the information resource.[176]

Examples of common access control mechanisms in use today include role-based access control, available in many advanced database management systems; simple file permissions provided in the UNIX and Windows operating systems;[206] Group Policy Objects provided in Windows network systems; and Kerberos, RADIUS, TACACS, and the simple access lists used in many firewalls and routers.[207]

To be effective, policies and other security controls must be enforceable and upheld. Effective policies ensure that people are held accountable for their actions.[208] The U.S. Treasury's guidelines for systems processing sensitive or proprietary information, for example, states that all failed and successful authentication and access attempts must be logged, and all access to information must leave some type of audit trail.[209]

Also, the need-to-know principle needs to be in effect when talking about access control. This principle gives access rights to a person to perform their job functions.[210] This principle is used in the government when dealing with difference clearances.[211] Even though two employees in different departments have a top-secret clearance, they must have a need-to-know in order for information to be exchanged. Within the need-to-know principle, network administrators grant the employee the least amount of privilege to prevent employees from accessing more than what they are supposed to.[212] Need-to-know helps to enforce the confidentiality-integrity-availability triad. Need-to-know directly impacts the confidential area of the triad.[213]

Information security uses cryptography to transform usable information into a form that renders it unusable by anyone other than an authorized user; this process is called encryption.[214] Information that has been encrypted (rendered unusable) can be transformed back into its original usable form by an authorized user who possesses the cryptographic key, through the process of decryption.[215] Cryptography is used in information security to protect information from unauthorized or accidental disclosure while the information is in transit (either electronically or physically) and while information is in storage.[92]

Cryptography provides information security with other useful applications as well, including improved authentication methods, message digests, digital signatures, non-repudiation, and encrypted network communications.[216] Older, less secure applications such as Telnet and File Transfer Protocol (FTP) are slowly being replaced with more secure applications such as Secure Shell (SSH) that use encrypted network communications.[217] Wireless communications can be encrypted using protocols such as WPA/WPA2 or the older (and less secure) WEP. Wired communications (such as ITU‑T G.hn) are secured using AES for encryption and X.1035 for authentication and key exchange.[218] Software applications such as GnuPG or PGP can be used to encrypt data files and email.[219]

Cryptography can introduce security problems when it is not implemented correctly.[220] Cryptographic solutions need to be implemented using industry-accepted solutions that have undergone rigorous peer review by independent experts in cryptography.[221] The length and strength of the encryption key is also an important consideration.[222] A key that is weak or too short will produce weak encryption.[222] The keys used for encryption and decryption must be protected with the same degree of rigor as any other confidential information.[223] They must be protected from unauthorized disclosure and destruction, and they must be available when needed.[224] Public key infrastructure (PKI) solutions address many of the problems that surround key management.[92]

The Software Engineering Institute at Carnegie Mellon University, in a publication titled Governing for Enterprise Security (GES) Implementation Guide, defines characteristics of effective security governance. These include:[239]

• An enterprise-wide issue
• Leaders are accountable
• Viewed as a business requirement
• Risk-based
• Roles, responsibilities, and segregation of duties defined
• Addressed and enforced in policy
• Adequate resources committed
• Staff aware and trained
• A development life cycle requirement
• Planned, managed, measurable, and measured
• Reviewed and audited

An incident response plan (IRP) is a group of policies that dictate an organizations reaction to a cyber attack. Once an security breach has been identified, for example by Network Intrusion Detection System (NIDS) or Host-Based Intrusion Detection System (HIDS) (if configured to do so), the plan is initiated.[240] It is important to note that there can be legal implications to a data breach. Knowing local and federal laws is critical.[241] Every plan is unique to the needs of the organization, and it can involve skill sets that are not part of an IT team.[242] For example, a lawyer may be included in the response plan to help navigate legal implications to a data breach.

As mentioned above every plan is unique but most plans will include the following:[243]

Good preparation includes the development of an Incident Response Team (IRT).[244] Skills need to be used by this team would be, penetration testing, computer forensics, network security, etc.[245] This team should also keep track of trends in cybersecurity and modern attack strategies.[246] A training program for end users is important as well as most modern attack strategies target users on the network.[243]

This part of the incident response plan identifies if there was a security event.[247] When an end user reports information or an admin notices irregularities, an investigation is launched. An incident log is a crucial part of this step.[248] All of the members of the team should be updating this log to ensure that information flows as fast as possible.[249] If it has been identified that a security breach has occurred the next step should be activated.[250]

In this phase, the IRT works to isolate the areas that the breach took place to limit the scope of the security event.[251] During this phase it is important to preserve information forensically so it can be analyzed later in the process.[252] Containment could be as simple as physically containing a server room or as complex as segmenting a network to not allow the spread of a virus.[253]

This is where the threat that was identified is removed from the affected systems.[254] This could include deleting malicious files, terminating compromised accounts, or deleting other components.[255][256] Some events do not require this step, however it is important to fully understand the event before moving to this step.[257] This will help to ensure that the threat is completely removed.[253]

This stage is where the systems are restored back to original operation.[258] This stage could include the recovery of data, changing user access information, or updating firewall rules or policies to prevent a breach in the future.[259][260] Without executing this step, the system could still be vulnerable to future security threats.[253]

In this step information that has been gathered during this process is used to make future decisions on security.[261] This step is crucial to the ensure that future events are prevented. Using this information to further train admins is critical to the process.[262] This step can also be used to process information that is distributed from other entities who have experienced a security event.[263]

Change management is a formal process for directing and controlling alterations to the information processing environment.[264][265] This includes alterations to desktop computers, the network, servers, and software.[266] The objectives of change management are to reduce the risks posed by changes to the information processing environment and improve the stability and reliability of the processing environment as changes are made.[267] It is not the objective of change management to prevent or hinder necessary changes from being implemented.[268][269]

Any change to the information processing environment introduces an element of risk.[270] Even apparently simple changes can have unexpected effects.[271] One of management's many responsibilities is the management of risk.[272][273] Change management is a tool for managing the risks introduced by changes to the information processing environment.[274] Part of the change management process ensures that changes are not implemented at inopportune times when they may disrupt critical business processes or interfere with other changes being implemented.[275]

Not every change needs to be managed.[276][277] Some kinds of changes are a part of the everyday routine of information processing and adhere to a predefined procedure, which reduces the overall level of risk to the processing environment.[278] Creating a new user account or deploying a new desktop computer are examples of changes that do not generally require change management.[279] However, relocating user file shares, or upgrading the Email server pose a much higher level of risk to the processing environment and are not a normal everyday activity.[280] The critical first steps in change management are (a) defining change (and communicating that definition) and (b) defining the scope of the change system.[281]

Change management is usually overseen by a change review board composed of representatives from key business areas,[282] security, networking, systems administrators, database administration, application developers, desktop support, and the help desk.[283] The tasks of the change review board can be facilitated with the use of automated work flow application.[284] The responsibility of the change review board is to ensure the organization's documented change management procedures are followed.[285] The change management process is as follows[286]

• Request: Anyone can request a change.[287][288] The person making the change request may or may not be the same person that performs the analysis or implements the change.[289][290] When a request for change is received, it may undergo a preliminary review to determine if the requested change is compatible with the organizations business model and practices, and to determine the amount of resources needed to implement the change.[291]
• Approve: Management runs the business and controls the allocation of resources therefore, management must approve requests for changes and assign a priority for every change.[292] Management might choose to reject a change request if the change is not compatible with the business model, industry standards or best practices.[293][294] Management might also choose to reject a change request if the change requires more resources than can be allocated for the change.[295]
• Plan: Planning a change involves discovering the scope and impact of the proposed change; analyzing the complexity of the change; allocation of resources and, developing, testing, and documenting both implementation and back-out plans.[296] Need to define the criteria on which a decision to back out will be made.[297]
• Test: Every change must be tested in a safe test environment, which closely reflects the actual production environment, before the change is applied to the production environment.[298] The backout plan must also be tested.[299]
• Schedule: Part of the change review board's responsibility is to assist in the scheduling of changes by reviewing the proposed implementation date for potential conflicts with other scheduled changes or critical business activities.[300]
• Communicate: Once a change has been scheduled it must be communicated.[301] The communication is to give others the opportunity to remind the change review board about other changes or critical business activities that might have been overlooked when scheduling the change.[302] The communication also serves to make the help desk and users aware that a change is about to occur.[303] Another responsibility of the change review board is to ensure that scheduled changes have been properly communicated to those who will be affected by the change or otherwise have an interest in the change.[304][305]
• Implement: At the appointed date and time, the changes must be implemented.[306][307] Part of the planning process was to develop an implementation plan, testing plan and, a back out plan.[308][309] If the implementation of the change should fail or, the post implementation testing fails or, other "drop dead" criteria have been met, the back out plan should be implemented.[310]
• Document: All changes must be documented.[311][312] The documentation includes the initial request for change, its approval, the priority assigned to it, the implementation,[313] testing and back out plans, the results of the change review board critique, the date/time the change was implemented,[314] who implemented it, and whether the change was implemented successfully, failed or postponed.[315][316]
• Post-change review: The change review board should hold a post-implementation review of changes.[317] It is particularly important to review failed and backed out changes. The review board should try to understand the problems that were encountered, and look for areas for improvement.[317]

Change management procedures that are simple to follow and easy to use can greatly reduce the overall risks created when changes are made to the information processing environment.[318] Good change management procedures improve the overall quality and success of changes as they are implemented.[319] This is accomplished through planning, peer review, documentation, and communication.[320]

ISO/IEC 20000, The Visible OPS Handbook: Implementing ITIL in 4 Practical and Auditable Steps[321] (Full book summary),[322] and ITIL all provide valuable guidance on implementing an efficient and effective change management program information security.[323]