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- 1. Chapter 8
Information Systems Controls for System Reliability— Part 1: Information Security
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
8-1
- 2. Learning Objectives
Discuss how the COBIT framework can be used to
develop sound internal control over an organization’s
information systems.
Explain the factors that influence information systems
reliability.
Describe how a combination of preventive, detective,
and corrective controls can be employed to provide
reasonable assurance about information security.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-2
- 3. AIS Controls
COSO and COSO-ERM address general internal control
COBIT addresses information technology internal control
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-3
- 4. Information for Management Should
Be:
Effectiveness
Information must be relevant
and timely.
Efficiency
Information must be produced
in a cost-effective manner.
Confidentiality
Sensitive information must be
protected from unauthorized
disclosure.
Integrity
Information must be accurate,
complete, and valid.
Availability
Information must be available
whenever needed.
Compliance
Controls must ensure
compliance with internal
policies and with external
legal and regulatory
requirements.
Reliability
Management must have
access to appropriate
information needed to
conduct daily activities and to
exercise its fiduciary and
governance responsibilities.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-4
- 6. COBIT Cycle
Management develops plans to organize information
resources to provide the information it needs.
Management authorizes and oversees efforts to acquire (or
build internally) the desired functionality.
Management ensures that the resulting system actually
delivers the desired information.
Management monitors and evaluates system performance
against the established criteria.
Cycle constantly repeats, as management modifies existing
plans and procedures or develops new ones to respond to
changes in business objectives and new developments in
information technology.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-6
- 7. COBIT Controls
210 controls for ensuring information integrity
Subset is relevant for external auditors
IT control objectives for Sarbanes-Oxley, 2nd Edition
AICPA and CICA information systems controls
Controls for system and financial statement reliability
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-7
- 8. Trust Services Framework
Security
Access to the system and its data is controlled and restricted to legitimate
users.
Confidentiality
Sensitive organizational information (e.g., marketing plans, trade secrets) is
protected from unauthorized disclosure.
Privacy
Personal information about customers is collected, used, disclosed, and
maintained only in compliance with internal policies and external regulatory
requirements and is protected from unauthorized disclosure.
Processing Integrity
Data are processed accurately, completely, in a timely manner, and only with
proper authorization.
Availability
The system and its information are available to meet operational and
contractual obligations.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-8
- 10. Security / Systems Reliability
Foundation of the Trust Services Framework
Management issue, not a technology issue
SOX 302 states:
CEO and the CFO responsible to certify that the
financial statements fairly present the results of the
company’s activities.
The accuracy of an organization’s financial
statements depends upon the reliability of its
information systems.
Defense-in-depth and the time-based model of information
security
Have multiple layers of control
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-10
- 11. Management’s Role in IS Security
Create security aware culture
Inventory and value company information resources
Assess risk, select risk response
Develop and communicate security:
Plans, policies, and procedures
Acquire and deploy IT security resources
Monitor and evaluate effectiveness
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-11
- 12. Time-Based Model
Combination of detective and corrective controls
P = the time it takes an attacker to break through the
organization’s preventive controls
D = the time it takes to detect that an attack is in progress
C = the time it takes to respond to the attack
For an effective information security system:
P > D + C
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-12
- 13. Steps in an IS System Attack
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-13
- 14. Mitigate Risk of Attack
Preventive Control
Detective Control
Corrective Control
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-14
- 15. Preventive Control
Training
User access controls (authentication and authorization)
Physical access controls (locks, guards, etc.)
Network access controls (firewalls, intrusion prevention
systems, etc.)
Device and software hardening controls (configuration
options)
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-15
- 16. Authentication vs.
Authorization
Authentication—verifies who a person is
1. Something person knows
2. Something person has
3. Some biometric characteristic
4. Combination of all three
Authorization—determines what a person can access
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-16
- 17. Network Access Control
(Perimeter Defense)
Border router
Connects an organization’s information system to the Internet
Firewall
Software or hardware used to filter information
Demilitarized Zone (DMZ)
Separate network that permits controlled access from the
Internet to selected resources
Intrusion Prevention Systems (IPS)
Monitors patterns in the traffic flow, rather than only inspecting
individual packets, to identify and automatically block attacks
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-17
- 19. Device and Software
Hardening (Internal Defense)
End-Point Configuration
Disable unnecessary features that may be vulnerable to
attack on:
Servers, printers, workstations
User Account Management
Software Design
Programmers must be trained to treat all input from external
users as untrustworthy and to carefully check it before
performing further actions.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-19
- 20. Detective Controls
Log Analysis
Process of examining logs to identify evidence of possible
attacks
Intrusion Detection
Sensors and a central monitoring unit that create logs of
network traffic that was permitted to pass the firewall and
then analyze those logs for signs of attempted or successful
intrusions
Managerial Reports
Security Testing
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-20
- 21. Corrective Controls
Computer Incident Response Team
Chief Information Security Officer (CISO)
Independent responsibility for information security assigned
to someone at an appropriate senior level
Patch Management
Fix known vulnerabilities by installing the latest updates
Security programs
Operating systems
Applications programs
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-21
- 22. Computer Incident Response
Team
Recognize that a problem exists
Containment of the problem
Recovery
Follow-up
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-22
- 23. New Considerations
Virtualization
Multiple systems are
run on one computer
Cloud Computing
Remotely accessed
resources
Software
applications
Data storage
Hardware
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 8-23
Risks
Increased exposure if
breach occurs
Reduced
authentication
standards
Opportunities
Implementing strong
access controls in the
cloud or over the server
that hosts a virtual
network provides good
security over all the
systems contained
therein
