Embed Size (px)
Citation preview
“How Secure is Your Corporation?"
One foot in ice water and one foot in boiling water does not mean that on average you are at room temperature.Corporations are not monolithic, and all parts
of the business don’t have or need the same level of security
Security is not an end state, nor can it be judged by measuring any single variable at any single point in time
Selling Security is Still a ChallengeIs the glass half empty, or is it half full?
Security is like the brakes on your car.Their function is to slow you down
But their purpose is to allow you to go fast.
Bill Malick, Gartner
Scope of SecuritySystem Security - Mostly Technical Issues - Hardware & Software Solutions, e.g.; Cryptography, Protocol, Security System
etc. Information Security - Mostly Managerial Issues - Business Solutions, e.g.; Organization, Culture (Behavior), Policy, Risk Management, Standards, Legal Rights
etc.
Causes of Information Damage Common Causes of damage
52%
10%
10%
15%
10%3%
Human errorDishonest peopleTechnical sabotageFireWaterTerrorism
Who causes damage
81%
13%6%
Current employees
Outsiders
Former employees
Types of computer crime
44%
16%
16%
12%
10% 2%
Money theft Damage of software
Theft of information Alteration of data
Theft of services Trespass
Information Security High dependence on information as a contributing
factor of success or failure, created the need for information security and control
Information security definition:
“preservation of confidentiality, integrity and availability of information and information systems”
The objective of information security is to ensure the continuity of business management and to reduce interruptions of business by preventing and minimizing the consequences of security incidents. Information security relates to all controls aimed at protecting the availability, integrity and confidentiality of information
Information Security Components
Reliability
Confidentiality / Exclusivity
Integrity
Availability
The degree to which the organization can depend uponan information system forits provision of information
Business Model for Information Security
Vulnerabilities
Threats
Legislation
Identity Mgmt Assurance
Controls
BusinessImpacts
ConfidentialityIntegrity
Availability
Assets
BusinessRisks
exposing To a loss of
causing
causing
which are mitigated by
which requirecausing
exploit +
which protect against
reduce
+
+
Security Systems Development Life Cycle(SSDLC)A systematic way of providing information securityPhases: -Phase 1: Investigation, including policy and
procedure etc. -Phase 2: Analysis, including risk management
etc. -Phase 3: Logical Design, including standards etc. -Phase 4: Physical Design, including technology
selection etc. -Phase 5: Implementation -Phase 6: Maintenance and Change
POLICY and PROCEDURE
Policy and Procedure A policy is typically a document that outlines specific requirements or
rules that must be met. In the information/network security realm, policies are usually point-
specific, covering a single area. For example, an “Acceptable Use” policy would cover the rules and regulations for appropriate use of the computing facilities.
A standard is typically a collections or system-specific or procedural-specific requirements that must be meet by everyone. For example, you might have a standard that describes to how to
harden a Windows NT workstation for placement on an external (DMZ) network.
People must follow this standard exactly if they wish to install a Windows NT workstation on an external network segment.
A guideline is typically a collection of system specific or procedural specific “suggestions” for best practice. They are not requirements to be met, but are strongly recommended.
Effective security policies make frequent references to standards and guidelines that exist within an organization.
A Security Policy FrameworkPolicies define appropriate behavior.Policies set the stage in terms of what tools
and procedures are needed.Policies communicate a consensus.Policies provide a foundation for HR action in
response to inappropriate behavior.Policies may help prosecute cases.
Importance of Security PoliciesSecurity policies are an absolute
must for any organization. They provide the virtual glue to
hold it all together. Policies lay the ground-work. Imagine a small city that did not
have any rules? What would life be like? The same applies to your organization .
Who and What to TrustTrust is a major principle underlying the
development of security policies.Initial step is to determine who gets access.Deciding on level of trust is a delicate
balancing act.Too much trust may lead to eventual security
problemsToo little trust may make it difficult to find
and keep employees or get jobs doneHow much should you trust people regarding
to their access or usage of computer and network resources?
Possible Trust Models
Trust everyone all of the time:easiest to enforce, but impracticalone bad apple can ruin the whole barrel
Trust no one at no time:most restrictive, but also impracticaldifficult to staff positions
Trust some people some of the time:exercise caution in amount of trust givenaccess is given out as neededtechnical controls are needed to ensure trust is
not violated
Why the Political Turmoil?People view policies as:
an impediment to productivitymeasures to control behavior
People have different views about the need for security controls.
People fear policies will be difficult to follow and implement.
Policies affect everyone within the organization.
Who Should Be Concerned?Users - policies will affect them the most.System support personnel - they will be
required to implement, comply with and support the policies.
Managers - they are concerned about protection of data and the associated cost of the policy.
Company lawyers and auditors - they are concerned about company reputation, responsibility to clients/customers.
The Policy Design ProcessChoose the policy development team.Designate a person or a group to serve as the
official policy interpreter.Decide on the scope and goals of the policy.
Scope should be a statement about who is covered by the policy.
Decide on how specific to make the policynot meant to be a detailed implementation plandon’t include facts which change frequently
The Policy Design ProcessA sample of people affected by the policy
should be provided an opportunity to review review and commentand comment.
A sampling of the support staff effected by policy should have an opportunity to review it.
Incorporate policy awarenesspolicy awareness as a part of employee orientation.
Provide a refresher overview courserefresher overview course on policies once or twice a year.
Basic Policy RequirementsPolicies must:
be implementable and enforceablebe concise and easy to understandbalance protection with productivity
Policies should:state reasons why policy is neededdescribe what is covered by the policiesdefine contacts and responsibilitiesdiscuss how violations will be handled
Level of Control Security needs and culture play major role.Security policies MUST balance level of
control with level of productivity.If policies are too restrictive, people will
find ways to circumvent controls.Technical controls are not always possible.You must have management commitment on
the level of control.
Policy StructureDependent on company size and goals.One large document or several small ones?
smaller documents are easier to maintain/updateSome policies appropriate for every site, others are
specific to certain environments.Some key policies:
acceptable useremote accessinformation protectionperimeter securitybaseline host/device security
The Acceptable Use PolicyDiscusses and defines the appropriate use of
the computing resources.Users should be required to read and sign
account usage policyaccount usage policy as part of the account request process.
A key policy that all sites should have.
Remote Access PolicyOutlines and defines acceptable methods of
remotely connecting to the internal network.Essential in large organization where
networks are geographically dispersed and even extend into the homes.
Should cover all available methods to remotely access internal resources:dial-in (SLIP, PPP)ISDN/frame relaytelnet/ssh access from internetcable modem/VPN/DSL
Information Protection Policy
Provides guidelines to users on the processing, storage and transmission of sensitive information.
Main goal is to ensure information is appropriately protected from modification or disclosure.
May be appropriate to have new employees sign policy as part of their initial orientation.
Should define sensitivity levels of information.
The Perimeter Security PolicyDescribes, in general, how perimeter security is maintained.
Describes who is responsible for maintaining it.
Describes how hardware and software changes to perimeter security devices are managed and how changes are requested and approved.
Virus Protection and Prevention PolicyProvides baseline requirements for the use of
virus protection software.Provides guidelines for reporting and
containing virus infections.Provides guidelines for several levels of virus
risk.Should discuss requirements for scanning
email attachments.Should discuss policy for the download and
installation of public domain software.
Virus Protection and Prevention PolicyShould discuss frequency of virus data file
updates.Should discuss testing procedures for
installation of new software.
Password PolicyProvides guidelines for how user level and
system level passwords are managed and changed.
Discusses password construction rules.Provides guidelines for how passwords are
protected from disclosure.Discusses application development
guidelines for when passwords are needed.Discusses the use of SNMP community
strings and pass-phrases.
Other Important PoliciesA policy which addresses forwarding of
email to offsite addresses.A policy which addresses wireless networks.A policy which addresses baseline lab
security standards.A policy which addresses baseline router
configuration parameters.A policy which addresses requirements for
installing devices on a dirty network.
Security Procedures Policies only define "what" is to be
protected. Procedures define "how" to protect
resources and are the mechanisms to enforce policy.
Procedures define detailed actions to take for specific incidents.
Procedures provide a quick reference in times of crisis.
Procedures help eliminate the problem of a single point of failure (e.g., an employee suddenly leaves or is unavailable in a time of crisis).
Configuration Management Procedure
Defines how new hardware/software is tested and installed.
Defines how hardware/software changes are documented.
Defines who must be informed when hardware and software changes occur.
Defines who has authority to make hardware and software configuration changes.
Data Backup and Off-site Storage ProceduresDefines which file systems are backed up.Defines how often backups are performed.Defines how often storage media is
rotated.Defines how often backups are stored off-
site.Defines how storage media is labeled and
documented.
Incident Handling ProcedureDefines how to handle anomaly investigation
and intruder attacks.Defines areas of responsibilities for members
of the response team.Defines what information to record and track.Defines who to notify and when.Defines who can release information and the
procedure for releasing the information. Defines how a follow-up analysis should be
performed and who will participate.
RISK MANAGEMENT
Risk
Risk is the likelihood of the occurrence of
a vulnerability multiplied by the value of the information asset minus the
percentage of risk mitigated by current controls plus the uncertainty of current knowledge of
the vulnerability
What is RiskA definable eventProbability of occurrenceImpact of occurrenceA risk occurs when the problem happensLoss expectancy that a threat might exploit a
vulnerability.
Relationship among different security componentsThreatAgent Threat
Vulnerability
RISK
Asset
ExposureSafeguard
Gives rise to
Exploits
Leads to
Can damage
And causes an
Can be counter measured by a
Directly affects
Risk
Well-Formed Risk Statement Well-Formed Risk Statement
ImpactWhat is the impact to the
business?
ProbabilityHow likely is the threat given the
controls?
AssetWhat are you
trying to protect?
AssetWhat are you
trying to protect?
ThreatWhat are you
afraid of happening?
ThreatWhat are you
afraid of happening?
VulnerabilityHow could the threat occur?
VulnerabilityHow could the threat occur?
MitigationWhat is currently
reducing the risk?
MitigationWhat is currently
reducing the risk?
Vulnerability IdentificationVulnerability – is a software, hardware, or procedural
weakness that may provide an attacker the open door to enter a system.
Specific avenues threat agents can exploit to attack an information asset are called vulnerabilities
Examine how each threat could be perpetrated and list organization’s assets and vulnerabilities
Process works best when people with diverse backgrounds within organization work iteratively in a series of brainstorming sessions
At the end of risk identification process, list of assets and their vulnerabilities is achieved
Risk MitigationUnderstand security riskUnderstand technologyAccept Risk
Documentation of risk acceptance is a form of mitigation.
Defer or transfer riskInsurance
Mitigate riskTechnology can mitigate risk
Risk Management Process
How to Develop a Security Risk Management Process?Security risk management process:
A process for identifying, prioritizing, and managing risk to an acceptable level within the organization
Developing a formal security risk management process must address the following: Threat response timeRegulatory complianceInfrastructure management costsRisk identification and assessment
(prioritization)
Successful Factors for Security Risk Management Process
Key factors to implementing a successful security risk management process include:Executive sponsorship Well-defined list of risk management
stakeholders Organizational maturity in terms of risk
managementAn atmosphere of open communications and
teamworkA holistic view of the organizationSecurity risk management team’s authority
Risk Management Process
Implementing Controls
Implementing Controls
33
Conducting Decision Support
Conducting Decision Support
22
Measuring Program Effectiveness
Measuring Program Effectiveness
44 Assessing RiskAssessing Risk11
Risk Assessment Flowchart
Step 1. System Characterization
Input Risk Assessment Activities Output
Step 2. Threat Identification
Step 3. Vulnerability Identification
Step 4. Control Analysis
Step 5. Likelihood Determination
Step 6. Impact Analysis• Loss of Integrity
• Loss of Availability • Loss of Confidentiality
Step 7. Risk Determination
Step 8.Control Recommendations
Step 9.Results Documentation
• Hardware / Software• System interfaces• Data and information• People • System mission
• History of system attack• Data from intelligence agencies, NIPC, OIG,FedCIRC, mass media,
• Reports from prior risk assessments• Any audit comments• Security requirements• Security test results
• Mission impact analysis• Asset criticality assessment• Data criticality• Data sensitivity
• Current controls• Planned controls
• Threat-source motivation• Threat capacity• Nature of vulnerability• Current controls
• System Boundary• System Functions• System and Data Criticality• System and Data Sensitivity
Impact Rating
Threat Statement
List of Potential Vulnerabilities
List of Current and Planned Controls
Likelihood Rating
• Likelihood of threat exploitation• Magnitude of impact• Adequacy of planned or current controls
Risks and Associated Risk Levels
Recommended Controls
Risk Assessment Report
Risk Mitigation FlowchartInput Risk Mitigation Activities Output
Step 1. Prioritize Actions
Step 2. Evaluate RecommendedControl Options
• Associated costs• Feasibility
Step 3. Conduct Cost-Benefit Analysis • Impact of implementing
• Impact of not implementing• Associated costs
Step 4. Select Controls
Step 5. Assign Responsibility
Step 6. Develop SafeguardImplementation Plan• Risks and Associated Risk Levels• Prioritized Actions• Recommended Controls• Selected Planned Controls• Responsible Persons• Start Date• Target Completion Date• Maintenance Requirements
Step 7.Implement SelectedControls
• Risk levels from the risk assessment report
• Risk assessment report
Actions ranking fromHigh to Low
Safeguard implementation plan
List of possible
controls
Cost-benefit analysis
Selected Controls
List ofresponsible persons
Residual Risks
Risk Analysis Method
Risk Management Risk Analysis(Identification + Assessment)
Goal Manage risks across business to acceptable level
Identify and prioritize risks
Cycle Overall program across all four phases
Single phase of risk management program
Schedule Scheduled activity Continuous activity
Alignment Aligned with budgeting cycles
Not applicable
Risk Analysis Method Two types of risk analysis:
Quantitative – attempts to assign real numbers to the costs of safeguards and the amount of damage that can take place
Qualitative – An analysis that judges an organization’s risk to threats, which is based on judgment, intuition, and the experience versus assigning real numbers to this possible risks and their potential loss; e.g.,
Analytical Hierarchy Process (AHP)
Steps of Quantitative Risk AnalysisAssign value to information assets
(tangible and intangible)Estimate potential loss per riskPerform a threat analysisDerive the overall loss potential per riskChoose safeguards / countermeasure for
each riskDetermine risk response (e.g. mitigation,
avoidance, acceptance)
Quantitative Risk Analysis Exposure Factor (EF) = Percentage of asset loss caused by
identified threat; ranges from 0 to 100%
Single Loss Expectancy (SLE) = Asset Value x Exposure Factor; 1,000,000 @ 10% likelihood = $100,000
Annualized Rate of Occurrence (ARO) = Estimated frequency a threat will occur with in a year and is characterized on an annual basis. A threat occurring once in 10 years has an ARO of 0.1; a threat occurring 50 times in a year has an ARO of 50
Annualized Loss Expectancy (ALE) = Single Loss Expectancy x Annualized Rate of Occurrence
Safeguard cost/benefit analysis = (ALE before implementing safeguard) – (ALE after implementing safeguard) – (annual cost of safeguard) == value of safeguard to the company
Quantitative Risk Analysis - Summary Pros
Uses probability concepts – the likelihood that an risk will occur or will not occur
The value of information is expressed in monetary terms with supporting rationale
Risk assessment results are derived and expressed in management speak
ConsPurely quantitative risk
analysis not possible because quantitative measures must be applied to qualitative elements
Can be less ambiguous but using numbers can give appearance of specificity that does not really exist
Huge amount of data must be gathered and managed
Qualitative Risk AnalysisDoes not assign numbers and monetary value
to components and losses.Walks through different scenarios of risk
possibilities and rank the seriousness of the threats for the sensitivity of the assets.
Identifying Qualitative RisksExpert InterviewsBrainstormingNominal Group TechniqueAffinity DiagramAnalogy Techniques
100%
4
12Example Qualitative Risk Matrix
Hostage / KidnapStrike / WalkoutHostile Takeover
Major Explosion
TerrorismIndustrial Espionage
0% Sabotage Comm. Disease
Flood
SuicideTelecomm Failure.
Maj. Operator Error
Child Care IncidentTransportation Incident
Minor Explosion
Neighbor Issue
Civil Unrest
Employee Violence
Tornado
Breach IT Security
Organized Crime
Blizzard
Bribery / Extortion
ProtestersInjury / DeathAccusation / Libel / Slander
Fog
Bomb ThreatEquipment Malfunc.Power Failure
Ice Storm
Media Investigation
Chemical Spill / Contamination
Major Fire
Class Action Lawsuit
Management Issues
Security Breach
Loss of IT / Virus
Major Electrical Storm
HIGH RISK
LOW RISK
MEDIUM HIGH
MEDIUM LOW
Qualitative Risk Analysis - Summary Pros
Is simple and readily understood and executed.
Provides a general indication of significant areas of risk that should be addressed
ConsIs difficult to enforce
in uniformity and consistency but provides some order of measurement
Is subjective in both process and metrics.
Can not provide cost/benefit analysis
Quantitative versus Qualitative
Quant.
Attributes Qual.
+ Independent & Objective Metrics -
+ Cost / Benefit analysis -
+ Monetary based -
- Amount of work, cost, time +
- Amount of information required +
+ Easily automated -
- Degree of guesswork +
+ Value of information understood -
+ Threat frequency and impact data required -
Corporate Risk Analysis Strategy
Corporate Risk Analysis Strategy
Corporate Risk Analysis Strategy
BaselineApproach
InformalApproach
DetailedApproach
CombinedApproach
Combined Approach
High Level Risk Analysis
Detailed Risk Analysis Baseline Approach
Selection of Safeguards
Risk Acceptance
IT System Security Policy
IT Security Plan
Baseline ApproachEstablish a minimum set of safeguards
to protect all or some IT systems of an organization
Achieved through the use of safeguard catalogues which suggest a set of safeguards to protect an IT system against the most common threats
The level of baseline security can be adjusted to the needs of the organization
Advantages Disadvantages
1. Minimum amount of resources
2. Cost-effective
1. Excessive level of security
2. A lack of security
3. Security relevant changes
Informal ApproachConduct informal pragmatic risk analysisExploit the knowledge and experience of
individuals
Advantages Disadvantages
1. Not require a lot of resources or time
2. Quicker than a detailed risk analysis
1. Missing some important details
2. Influenced by subjective views
Detailed ApproachInvolves the identification of the related
risks, and an assessment of their magnitude for all IT systems
The result of the analysis should be savedAsset and their valuesThreat, vulnerability, and risk levelsSafeguards identified
Advantages Disadvantages
1. Appropriate safeguards are
identified for all systems
2. Management of security changes
1. A considerable amount of time,
effort, and expertise
Combined ApproachFirst it is necessary to conduct an initial high
level risk analysis to identify which approach (baseline or detailed approach) is appropriate for each IT system
Input for the decision as to which approach is suitable for which IT system:The business values of the IT systemsThe level of investment in this IT systemThe asset’s value of the IT system
Advantages Disadvantages
1. Provide a good balance between(1) Minimizing the time and effort spent in identifying safeguards
(2) Ensuring the high risk systems are appropriately protected.
1. Some systems may not be
identified as requiring
detailed risk analysis
The Process of Risk AnalysisEstablishment of Review Boundary
Identification of Assets
Valuation of Assetsand Establishment of Dependencies Between Assets
ThreatAssessment
VulnerabilityAssessment
Identificationof Existing/Planning
Safeguards
Assessment of Risks
Selection of Safeguards
Risk Acceptance
IT System Security Policy
IT Security Plan
IdentificationReview ofConstraints
NoYes
Detailed Approach
Risk Management
INFORMATION SECURITY STANDARD
IntroductionISO 17799/BS 7799-1 is an international
standard that sets out the requirements of good practice for Information Security Management.
ISO 27001/BS 7799-2 defines the specification for an Information Security Management System (ISMS).
- The scope of an ISMS includes:
peopleprocesses
IT Systems Policies
History of ISMS Standards
ISO17799:2000International
BS7799-1:1999
BS7799-2:1999
UK
BS7799-Part 2: 2002
BS7799-1:2000
ISO17799:2005
ISO27001:2005
BS7799:1995
= copy/translation
= revision
What is BS7799-1 / ISO 17799?
The goal of BS7799-1 / ISO 17799 is to “provide a common base for developing organizational security standards and effective security management practice and to provide confidence in inter-organizational dealings.”
Who is BS7799-1/ISO 17799 for?
BS7799-1 / ISO 17799 meets the needs of organizations and companies of all types, both private and public.
For any organization that stores confidential information on internal or external systems, depends on such systems to run its operations, or indeed wishes to demonstrate its information security by conforming to a known standard, BS7799-1 / ISO 17799 would be of very great interest.
The Eleven Key Context of ISO 17799 Security policy - This provides management direction
and support for information security Organization of information security - To help you
manage information security within the organization Asset management - To help you identify your assets
and appropriately protect them Human resources security - To reduce the risks of
human error, theft, fraud or misuse of facilities Physical and environmental security - To prevent
unauthorized access, damage and interference to business premises and information
Communications and operations management - To ensure the correct and secure operation of information processing facilities
The Eleven Key Context of ISO 17799 (cont’d)Access control - To control access to informationInformation systems acquisition, development and
maintenance - To ensure that security is built into information systems
Information security incident management-To make sure that all information security events and weaknesses can be reported and solve effectively.
Business continuity management - To counteract interruptions to business activities and to protect critical business processes from the effects of major failures or disasters
Compliance - To avoid breaches of any criminal and civil law, statutory, regulatory or contractual obligations, and any security requirement
Information Security Management System (ISMS)
Definition: that part of the overall management system,
based on a business risk approach, to - establish, - implement, - operate, - monitor, - maintain and- improve information security
The management system includes organizational structure, policies, planning activities, responsibilities, practices, procedures, processes and resources
Plan-Do-Check-Act Cycle (PDCA)
Interested parties
Interested parties
Establish ISMS Context & Risk
Assessment
Plan
Design and Implement ISMS
Do
Maintain and Improve the ISMS
Act
Monitor and Review ISMS
Check
Information security
requirements and expectations
Managed information
security
Development, Maintenance and
Improvement cycle
PDCA
Establish the ISMS
Define the scope of the ISMS Define an ISMS policy Define a systematic approach to risk management Identify the risks Assess the risks Identify and evaluate options for the treatment of risks Select control objectives and controls for the treatment of
risks Prepare a Statement of Applicability Obtain management approval for residual risks and
authorization to implement and operate the ISMS
PDCAImplement and operate the ISMS
Formulate a risk treatment plan and its documentation, including planned process and detailed procedures
Implement the risk treatment plan planned controls
Implement training and awareness programs Manage operations and resources Implement procedures and controls to detect
and response to security incidents
PDCA
Monitor and review the ISMS
Execute monitoring proceduresUndertake regular reviewsReview level of residual riskConduct internal auditsUndertake a management reviewRecord actions and events
PDCA
Maintain and improve the ISMS
Implement the identified improvements
Take appropriate corrective and preventive actions
Communicate results Ensure effectiveness
ISO27001 versus ISO17799
ISO27001
formal standardcertification
possiblerequirements for a
management system
requirements for controls(if applicable)
ISO 17799
• code of practice(set of best practices)
• implementation advice and guidance
What are ISO 17799 and ISO 27001 not
• limited to information technology
• a security checklist
• an insurance policy against security breaches
• an audit method
• a risk analysis method
