User:Courtneyscott/Information security audit

Background

An information security audit is an audit on the level of information security in an organization. It is an independent review and examination of system records, activities and related documents. These audits are intended to improve the level of information security, avoid improper information security designs, and optimize the efficiency of the security safeguards and security processes.

Within the broad scope of auditing information security there are multiple types of audits, multiple objectives for different audits, etc. Most commonly the controls being audited can be categorized to technical, physical and administrative. Auditing information security covers topics from auditing the physical security of data centers to auditing the logical security of databases, and highlights key components to look for and different methods for auditing these areas.

When centered on the Information technology (IT) aspects of information security, it can be seen as a part of an information technology audit. It is often then referred to as an information technology security audit or a computer security audit. However, information security encompasses much more than IT.

The Audit Process

Step 1: Preliminary Audit Assessment

The auditor is responsible for assessing the current technological maturity level of a company during the first stage of the audit. This stage is used to assess the current status of the company and helps identify the required time, cost and scope of an audit. First, you need to identify the minimum security requirements:

• Security policy and standards
• Organizational and Personal security
• Communication, Operation and Asset management
• Physical and environmental security
• Access control and Compliance
• IT systems development and maintenance
• IT security incident management
• Disaster recovery and business continuity management
• Risk management

Step 2: Planning & Preparation

The auditor should plan a company's audit based on the information found in Step 1. Planning an audit helps the auditor obtain sufficient and appropriate evidence for each company's specific circumstances. It helps predict audit costs at a reasonable level, assign the proper manpower and time line and avoid misunderstandings with clients.

An auditor should be adequately educated about the company and its critical business activities before conducting a data center review. The objective of the data center is to align data center activities with the goals of the business while maintaining the security and integrity of critical information and processes. To adequately determine whether the client's goal is being achieved, the auditor should perform the following before conducting the review:

• Meet with IT management to determine possible areas of concern
• Review the current IT organization chart
• Review job descriptions of data center employees
• Research all operating systems, software applications, and data center equipment operating within the data center
• Review the company's IT policies and procedures
• Evaluate the company's IT budget and systems planning documentation
• Review the data center's disaster recovery plan

Step 3: Establishing Audit Objectives

The next step in conducting a review of a corporate data center takes place when the auditor outlines the data center audit objectives. Auditors consider multiple factors that relate to data center procedures and activities that potentially identify audit risks in the operating environment and assess the controls in place that mitigate those risks. After thorough testing and analysis, the auditor is able to adequately determine if the data center maintains proper controls and is operating efficiently and effectively.

Following is a list of objectives the auditor should review:

• Personnel procedures and responsibilities, including systems and cross-functional training
• Change management processes are in place and followed by IT and management
• Appropriate backup procedures are in place to minimize downtime and prevent loss of important data
• The data center has adequate physical security controls to prevent unauthorized access to the data center
• Adequate environmental controls are in place to ensure equipment is protected from fire and flooding

Step 4: Performing the Review

The next step is collecting evidence to satisfy data center audit objectives. This involves traveling to the data center location and observing processes and within the data center. The following review procedures should be conducted to satisfy the predetermined audit objectives:

• Data center personnel – All data center personnel should be authorized to access the data center (key cards, login ID's, secure passwords, etc.). Datacenter employees are adequately educated about data center equipment and properly perform their jobs. Vendor service personnel are supervised when doing work on data center equipment. The auditor should observe and interview data center employees to satisfy their objectives.
• Equipment – The auditor should verify that all data center equipment is working properly and effectively. Equipment utilization reports, equipment inspection for damage and functionality, system downtime records and equipment performance measurements all help the auditor determine the state of data center equipment. Additionally, the auditor should interview employees to determine if preventative maintenance policies are in place and performed.
• Policies and Procedures – All data center policies and procedures should be documented and located at the data center. Important documented procedures include data center personnel job responsibilities, back up policies, security policies, employee termination policies, system operating procedures and an overview of operating systems.
• Physical security / environmental controls – The auditor should assess the security of the client's data center. Physical security includes bodyguards, locked cages, man traps, single entrances, bolted-down equipment, and computer monitoring systems. Additionally, environmental controls should be in place to ensure the security of data center equipment. These include Air conditioning units, raised floors, humidifiers and uninterruptible power supply.
• Backup procedures – The auditor should verify that the client has backup procedures in place in the case of system failure. Clients may maintain a backup data center at a separate location that allows them to instantaneously continue operations in the instance of system failure.

Step 5: Preparing the Audit Report

After the audit examination is completed, the audit findings and suggestions for corrective actions can be communicated to responsible stakeholders in a formal meeting. This ensures better understanding and support of the audit recommendations. It also gives the audited organization an opportunity to express its views on the issues raised.

Writing a report after such a meeting and describing where agreements have been reached on all audit issues can greatly enhance audit effectiveness. Exit conferences also help finalize recommendations that are practical and feasible.

Step 6: Issuing the Review Report

The data center review report should summarize the auditor's findings and be similar in format to a standard review report. The review report should be dated as of the completion of the auditor's inquiry and procedures. It should state what the review entailed and explain that a review provides only "limited assurance" to third parties.

Typically, a data center review report consolidates the entirety of the audit. It also offers recommendations surrounding proper implementation of physical safeguards and advises the client on appropriate roles and responsibilities of its personnel. Its contents may include:

• The auditors’ procedures and findings
• The auditors’ recommendations
• Objective, scope, and methodologies
• Overview/conclusions

The report may optionally include rankings of the security vulnerabilities identified throughout the performance of the audit and the urgency of the tasks necessary to address them. Rankings like “high”, “low”, and “medium” can be used to describe the imperativeness of the tasks.

Who Performs Audits

Generally, computer security audits are performed by:

1. Federal or State Regulators
   • Information security audits would primarily be prepared by the partners of these regulators.
   • Examples include: certified accountants, Cybersecurity and Infrastructure Security Agency (CISA). Federal Office of Thrift Supervision (OTS), Office of the Comptroller of the Currency (OCC), U.S. Department of Justice (DOJ), etc.
2. Corporate Internal Auditors
   • If the information security audit is an internal audit, it may be performed by internal auditors employed by the organization.
   • Examples include: certificated accountants, Cybersecurity and Infrastructure Security Agency (CISA), Certified Internet Audit Professional (CIAP).
3. External Auditors
   • Typically, third-party experts employed by an independent organization and specializing in the field of data security are hired when state or federal auditors are not accessible.
4. Consultants
   • Outsourcing the technology auditing where the organization lacks the specialized skill set.

Certifications in Security  

Information systems audits combine the efforts and skill sets from the accounting and technology fields. Professionals from both fields rely on one another to ensure the security of the information and data.With this collaboration, the security of the information system has proven to increase over time. In relation to the information systems audit, the role of the auditor is to examine the company’s controls of the security program. Furthermore, the auditor discloses the operating effectiveness of these controls in an audit report. The Information Systems Audit and Control Association (ISACA), an Information Technology professional organization, promotes gaining expertise through various certifications. The benefits of these certifications are applicable to external and internal personnel of the system. Examples of certifications that are relevant information security audits include:

• Certified Information Systems Manager (CISM)
• Certified in Risk and Information Systems Control (CRISC)
• Certified in the Governance of Enterprise IT (CGEIT)
• Certified Information System Auditor (CISA)
• CSX (Cybersecurity Nexus Fundamentals)
• CSXP (Cybersecurity Nexus Practitioner)

The Audited Systems

Network Vulnerabilities

• Interception: Data that is being transmitted over the network is vulnerable to being intercepted by an unintended third party who could put the data to harmful use.
• Availability: Networks have become wide-spanning, crossing hundreds or thousands of miles which many rely on to access company information, and lost connectivity could cause business interruption.
• Access/entry point: Networks are vulnerable to unwanted access. A weak point in the network can make that information available to intruders. It can also provide an entry point for viruses and Trojan horses.

Controls

• Interception controls: Interception can be partially deterred by physical access controls at data centers and offices, including where communication links terminate and where the network wiring and distributions are located. Encryption also helps to secure wireless networks.
• Availability controls: The best control for this is to have excellent network architecture and monitoring. The network should have redundant paths between every resource and an access point and automatic routing to switch the traffic to the available path without loss of data or time.
• Access/entry point controls: Most network controls are put at the point where the network connects with an external network. These controls limit the traffic that passes through the network. These can include firewalls, intrusion detection systems, and antivirus software.

The auditor should ask certain questions to better understand the network and its vulnerabilities. The auditor should first assess the extent of the network and how it is structured. A network diagram can assist the auditor in this process. The next question an auditor should ask is what critical information this network must protect. Things such as enterprise systems, mail servers, web servers, and host applications accessed by customers are typically areas of focus. It is also important to know who has access and to what parts. Do customers and vendors have access to systems on the network? Can employees access information from home? Lastly, the auditor should assess how the network is connected to external networks and how it is protected. Most networks are at least connected to the internet, which could be a point of vulnerability. These are critical questions in protecting networks.

Segregation of Duties

When you have a function that deals with money either incoming or outgoing it is very important to make sure that duties are segregated to minimize and hopefully prevent fraud. One of the key ways to ensure proper segregation of duties (SoD) from a systems perspective is to review individuals’ access authorizations. Certain systems such as SAP claim to come with the capability to perform SoD tests, but the functionality provided is elementary, requiring very time-consuming queries to be built and is limited to the transaction level only with little or no use of the object or field values assigned to the user through the transaction, which often produces misleading results. For complex systems such as SAP, it is often preferred to use tools developed specifically to assess and analyze SoD conflicts and other types of system activity. For other systems or for multiple system formats you should monitor which users may have superuser access to the system giving them unlimited access to all aspects of the system. Also, developing a matrix for all functions highlighting the points where proper segregation of duties has been breached will help identify potential material weaknesses by cross-checking each employee's available accesses. This is as important if not more so in the development function as it is in production. Ensuring that people who develop the programs are not the ones who are authorized to pull it into production is key to preventing unauthorized programs into the production environment where they can be used to perpetrate fraud.

Types of Audits

Logical Security Audit

The first step in an audit of any system is to seek to understand its components and its structure. When auditing logical security the auditor should investigate what security controls are in place, and how they work. In particular, the following areas are key points in auditing logical security:

• Passwords: Every company should have written policies regarding passwords, and employees' use of them. Passwords should not be shared and employees should have mandatory scheduled changes. Employees should have user rights that are in line with their job functions. They should also be aware of proper log on/ log off procedures. Also helpful are security tokens, small devices that authorized users of computer programs or networks carry to assist in identity confirmation. They can also store cryptographic keys and biometric data. The most popular type of security token (RSA's SecurID) displays a number that changes every minute. Users are authenticated by entering a personal identification number and the number on the token.
• Termination Procedures: Proper termination procedures so that, old employees can no longer access the network. This can be done by changing passwords and codes. Also, all id cards and badges that are in circulation should be documented and accounted for.
• Special User Accounts: Special User Accounts and other privileged accounts should be monitored and have proper controls in place.
• Remote Access: Remote access is often a point where intruders can enter a system. The logical security tools used for remote access should be very strict. Remote access should be logged.

Behavioral Audit

Vulnerabilities in an organization's  IT systems are often not attributed to technical weaknesses, but rather related to individual behavior of employees within the organization. A simple example of this is users leaving their computers unlocked or being vulnerable to phishing attacks. As a result, a thorough InfoSec audit will frequently include a penetration test in which auditors attempt to gain access to as much of the system as possible, from both the perspective of a typical employee as well as an outsider.

A behavioral audit ensures preventative measures are in place such as a phishing webinar, where employees are made aware of what phishing is and how to detect it.

The employee’s honesty is also important to ensure integrity of the company and to make sure they are upholding the company's policies, specifically the ones that are meant to make a company susceptible to human mistakes. The honesty of employees can be reinforced by a system of internal controls as well as behavioral audits. It includes documentation of employees' understanding of policies and procedures, and continuous monitoring.

System and process assurance audits combine elements from IT infrastructure and application/information security audits and use diverse controls in categories such as Completeness, Accuracy, Validity (V) and Restricted access (CAVR).

Encryption & IT Audit

In assessing the need for a client to implement encryption policies for their organization, the Auditor should conduct an analysis of the client's risk and data value. Companies with multiple external users, e-commerce applications, and sensitive customer/employee information should maintain rigid encryption policies aimed at encrypting the correct data at the appropriate stage in the data collection process.

Auditors should continually evaluate their client's encryption policies and procedures. Companies that are heavily reliant on e-commerce systems and wireless networks are extremely vulnerable to theft and loss of critical information in transmission. Policies and procedures should be documented and carried out to ensure that all transmitted data is protected.

The auditor should verify that management has controls in place over the data encryption management process. Access to keys should require dual control, keys should be composed of two separate components and should be maintained on a computer that is not accessible to programmers or outside users. Furthermore, management should attest that encryption policies ensure data protection at the desired level and verify that the cost of encrypting the data does not exceed the value of the information itself. All data that is required to be maintained for an extensive amount of time should be encrypted and transported to a remote location. Procedures should be in place to guarantee that all encrypted sensitive information arrives at its location and is stored properly. Finally, the auditor should attain verification from management that the encryption system is strong, not attackable, and compliant with all local and international laws and regulations.

Summary

By and large, the two concepts of application security and segregation of duties are both in many ways connected and they both have the same goal, to protect the integrity of the companies’ data and to prevent fraud. For application security, it has to do with preventing unauthorized access to hardware and software through having proper security measures both physical and electronic in place. With segregation of duties, it is primarily a physical review of individuals’ access to the systems and processing and ensuring that there are no overlaps that could lead to fraud.