1 Risk Management Identifying and Assessing Risk EECS 711 Philip Mein "Prakash" Pallavur...

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Risk ManagementIdentifying and Assessing Risk

EECS 711

Philip Mein

"Prakash" Pallavur Sankaranaraynan

Annette Tetmeyer

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Outline• Introduction• Risk Management• Risk Identification• Risk Assessment• Documenting the Results of Risk Assessment

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In the News• “Imprudent curiosity” and ample warning?

"Every single time they access a computer there's a reminder that comes up that says:

The information you are about to access has Privacy Act restrictions on it and you are acknowledging that you have a need to

know in order to do your job to access this file; and that if you are accessing it in an

unauthorized manner, then there are potential penalties."

http://www.cnn.com/2008/POLITICS/03/21/passport.breach/index.html

http://www.cnn.com/2008/POLITICS/03/21/passport.breach/index.html

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Introduction

• Information security departments are created primarily to manage IT risk

• Risk management program has two formal processes – Risk identification and assessment – Risk control

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Knowing Ourselves

• Identify, Examine and Understand – information at rest, in motion, and in use

(stored, transmitted, and processed)

• Initiate an in-depth risk management program

• Risk management is a process– It is the safeguards and controls that are

devised and implemented (due diligence is required)

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Knowing the Enemy

• Identify, examine, and understand – the threats

• Managers must be prepared – to fully identify those threats that pose risks to the

organization and the security of its information assets

• Risk management is the process – of assessing the risks to an organization’s

information and determining how those risks can be controlled or mitigated

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Risk Management• The process concerned with identification,

measurement, control and minimization of security risks in information systems to a level commensurate with the value of the assets protected (NIST)

Implement RiskManagement

Actions

Implement RiskManagement

Actions

Re-evaluatethe Risks

Re-evaluatethe Risks

Identifythe

Risk Areas

Identifythe

Risk Areas

Assess the Risks

Assess the Risks

Develop RiskManagement

Plan

Develop RiskManagement

Plan

Risk Management

CycleRisk Assessment

Risk Control (Mitigation)

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Accountability for Risk Management

• All three communities of interest bear responsibility (IT, InfoSec, Management & Users)– Evaluating risk controls– Determining which control options are cost-

effective – Acquiring or installing appropriate controls– Overseeing processes to ensure that controls

remain effective – Identifying risks– Assessing risks– Summarizing findings

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Risk Identification Process

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Risk Identification

• Risk identification – begins with the process of self-examination

• Managers – identify the organization’s information

assets, – classify them into useful groups, and – prioritize them by their overall importance

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Creating an Inventory of Information Assets

• Identify information assets– people, procedures, data and information,

software, hardware, and networking elements

– values will be assigned later in the process

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Organizational Assets

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Identifying Hardware, Software, and Network Assets• Many organizations use purchased

asset inventory systems

• Determine which attributes of each of these information assets should be tracked– Will depend on the needs of the

organization and – its risk management efforts

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Attributes for Assets• Potential attributes:

– Name– IP address– MAC address– Asset type– Manufacturer name– Manufacturer’s model or part number

• Software version, update revision, – Physical location– Logical location– Controlling entity

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Commercial Products

• Altiris

• Novell Zenworks

• Microsoft SMS

• CA Asset Management

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Identifying People, Procedures, and Data Assets

• Whose Responsibility ?– managers who possess the necessary

knowledge, experience, and judgment

• Recording– use reliable data-handling process

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People, Procedures, and Data AssetsSuggested Attributes

• People– Position

name/number/ID– Supervisor

name/number/ID– Security clearance

level– Special skills

Procedures Description Intended purpose Software/hardware/

networking elements to which it is tied

Location where it is stored for reference

Location where it is stored for update purposes

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People, Procedures, and Data AssetsSuggested Attributes

• Data– Classification– Owner/creator/manager– Size of data structure– Data structure used– Online or offline– Location– Backup procedures

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Classifying and Categorizing Assets

• Determine whether its asset categories are meaningful – After initial inventory is assembled

• Inventory should also reflect sensitivity and security priority assigned to each asset

• A classification scheme categorizes these information assets based on their sensitivity and security needs– One exmple: confidential, internal, and public

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Classifying and Categorizing Assets (Continued)

• Categories– designates level of protection needed for a

particular information asset

• Classification categories must be comprehensive and mutually exclusive

• Personnel may require alternative classification– identifies the clearance needed to use the asset

type– Need-to-know, right-to-update

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Assessing Values for Information Assets

• Assign a relative value – to ensure that the most valuable information assets are

given the highest priority, for example:• Which is the most critical to the success of the organization? • Which generates the most revenue? • Which generates the highest profitability? • Which is the most expensive to replace? • Which is the most expensive to protect? • Whose loss or compromise would be the most embarrassing or

cause the greatest liability?

• Final step in the Risk Identification process is to list the assets in order of importance– Can use a weighted factor analysis worksheet

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Weighted Factor Analysis Worksheet Risk Management for IT Systems

(NIST SP 800-30)

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Data Classification Model

• Data owners must classify information assets for which they are responsible and review the classifications periodically

• Example:– Public– For official use only– Sensitive– Classified

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Data Classification Model

• US Military uses a five-level classification scheme as defined in Executive Order 12958: – Unclassified Data– Sensitive But Unclassified (SBU) Data– Confidential Data– Secret Data– Top Secret Data

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Security Clearances

• Personnel Security Clearance Structure:– Complement to data classification scheme – Each user of information asset is assigned an

authorization level that indicates level of information classification he or she can access

• Most organizations have developed a set of roles and corresponding security clearances– Individuals are assigned into groups that correlate

with classifications of the information assets they need for their work

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Management ofClassified Information Assets

• Managing an information asset includes – the storage, distribution, portability, and

destruction of that information asset

• Information asset that has a classification designation other than unclassified or public:– Must be clearly marked as such – Must be available only to authorized individuals

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Management ofClassified Information Assets

• Clean Desk policy– To maintain confidentiality of classified

documents, managers can implement a clean desk policy

• Destruction of sensitive material– When copies of classified information are

no longer valuable or too many copies exist, care should be taken to destroy them properly to discourage dumpster diving

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Threat Identification

• Assess potential weaknesses in information assets

• Requires experience and good judgment

• Cannot assume that each and every threat will lead to an attack

• Need to prioritize and identify threats and threat agents

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Threat Assessment

• Which threats present a danger to this organization’s information assets in its current environment?– Eliminate any threats that do not impact

your organization.– Provide specific examples for the threats

those that do impact

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• Which threats represent the gravest danger to the organization’s information assets?– Consider probability of threat, amount of

damage, or frequency that an attack can occur

– Based on existing level of preparedness and used for improving information security strategy

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Top three threats identified by top computing executives:

• Deliberate software attacks• Technical software failures or errors• Acts of human error or failure

• Do you agree?

Threats to Information Security: Survey of Industry

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Threat IdentificationTop four types of attack or misuse:• Virus• Laptop/mobile theft• Insider abuse of Net access• Unauthorized access to information

• Any thoughts?

CSI/FBI Survey Results for Types of Attack or Misuse (1999-2006)2007 updates availables

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Frequency of Attacks

Ask the following questions:• How much would it cost to recover from

a successful attack?– Can rank potential costs (1-5) or assign

raw values– Want rough assessments, not full blown

analysis

• Which threats would require the greatest expenditure to prevent?

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Frequency of Attacks

• Detected attacks have been decreasing*

• Some organizations also do not know if they have been attacked or not

*CSI Survey 2007 (http://gocsi.com )

http://gocsi.com/

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Vulnerability Assessment

• Create asset-threat pairs.• Use the table of threats to analyze and list

possible vulnerabilities for each specific asset.

• Process can be somewhat subjective and based on experience/knowledge.

• Use teams with diverse backgrounds (specialists, management, technically proficient users) to conduct assessment.

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Threat Vulnerability Asset Worksheet (TVA)

• TVA => Prioritized list of assets and their vulnerabilities + Threats prioritized by weights

• X-axis => Prioritized set of assets with most valuable asset listed on the extreme left

• Y-axis => Prioritized set of threats with most important or dangerous threat listed at the top

• A grid that provides a convenient method of examining the exposure of assets

• Provides a simplistic vulnerability assesment• Created in “triples”

EECS 711 Spring 2008 Chapter 737

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Risk Assessment Process• Many believe the most difficult aspect of risk

assessment is uncovering the large number of systems and their configuration vulnerabilities that put a system at risk

• In reality the challenge is deciding organization wide the value of information and intellectual property

• Without this knowledge and the systems that ensure this information flows it is impossible to make a decision on how much can reasonably spent in protecting this information

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Risk Assessment Process (contd)

• In assessing risk one must know what needs to be protected and how much the information is worth

• Challenges:– What system needs protection?– Which vulnerabilities pose the greates

threat?


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Risk Assessment

• Process of assessing relative risk for each vulnerability

• Assigns a risk rating or score to each vulnerability

• No meaning in absolute terms but helps gauge relative risk associated with each vulnerable information asset

• Model to evaluate risk for each info asset


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Risk Assessment (contd)

Risk Rating = Likelihood of occurrence of a vulnerability x Value of information asset - % of risk mitigated by current controls + Uncertainty of current knowledge of the vulnerability


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• Likelihood of vulnerability– Probability that a specific vulnerability will be

exploited– NIST 800-30 recommends values between

0.1(low) and 1.0(high)– Cannot be 0, because vulnerabilities with a

likelihood of 0 should have been removed from the asset vulnerability list

– External references for many asset/vulnerability combinations already exist and should be used whenever possible


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• Potential loss– Done by weighted scores based on the

value of information asset– NIST 800-30 assigns weights in broad

categories 100(high value) 1(low value) 50(medium value)

– Other scales use 1 to 10 or assigned values of 1(low), 3(medium) and 5(high)


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• Percentage of risk mitigated by current controls– If vulnerability is fully managed by an

existing control, it can set aside– If vulnerability is partially controlled,

estimate what % of vulnerability has been controlled


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• Uncertainty– It is not possible to know everything about

an vulnerability– How likely is an attack against a

vulnerability– How great of an impact would a successful

attack have on an organization– It is an estimate made by the manager

using good judgment and experience


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• Identify possible controls– For each threat and its associated

vulnerabilities that have residual risk create a list of control ideas

– List begins with identifying existing controls, this is to identifying areas of residual risk that may or may not need to be reduced

– Residual risk is risk that remains even after existing control has been applied


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Controls

• Three categories of controls exist:– Policies– Programs (like education, training and

awareness)– Technical controls (security technologies)


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Access Controls

• Addresses the admission of users into a trusted area of an organization

• Each category of access control regulates access to a particular type or collection of information

• Types of access controls:– Mandatory Access Control (MAC)– Non-discretionary Control– Discretionary Control (DAC)


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Access ControlsMAC• Required and Structured• Coordinated with data classification scheme• When implemented users and data owners have limited control over their

access to information access• Rates information and each user to a specific level of information• Rating is called sensitivity level and a variation of this is called Lattice Based

Access Control• In lattice based access controls users are assigned a matrix of authorizations

for particular areas of access• Structure contains subjects and objects and boundaries associated with each

subject/object pair is clearly demarked• Column attributes associated with objects are called ACL’s• Row attributes associated with subjects are called Capability Tables


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Access Controls

• Non Discretionary Controls– Determined by central authority

– Can be based on roles a user plays in an organization called roles based access control

– Can be based on set of tasks tied to a certain assignment or responsibility called task based access control

– It makes it easier to maintain control and restrictions if individuals performing the task or role changes frequently


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Access Controls

• Discretionary Access Control (DAC)– Implemented at the discretion or option of

the users– Ability to share resources in a peer to peer

configuration– Allows users to control and possibly

provide access to information or resources at their disposal


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Documenting Results of Risk Assessment

• Ranked vulnerability risk worksheet– Asset: List of each vulnerable asset– Asset Impact: Shows results for the asset from the

weighted factor analysis (1-100)– Vulnerability: List each uncontrolled vulnerability

for that asset– Vulnerability Likelihood: Likelihood of the

realization of the vulnerability by threat agent as indicated in the vulnerability analysis step (0.1-1.0)

– Risk Rating Factor: Calculated by multiplying the asset impact and a vulnerability’s likelihood


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Documenting Results of Risk Assessment

• Risk identification and assessment deliverables– Information asset classification worksheet

(information assets and impact on or value to organization)

– Weighted criteria analysis worksheet (assigns a ranked value or impact weight to each asset)

– TVA worksheet– Ranked vulnerability risk worksheet (assigns a

risk rating ranked value to each uncontrolled asset vulnerability pair)


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Conclusion

• Risk management examines and documents an organizations information assets to classify, prioritize and assess risk that needs to be controlled

• The presence of uncontrolled vulnerabilities in high ranking assets are the 1st priority of new controls as part of risk management

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