Chapter 8 – Administering Security Security Planning Risk Analysis Security Policies Physical Security

Security Planning Policy Current state – risk analysis Requirements Recommended controls Accountability Timetable Continuing attention

Security Planning - Policy Who should be allowed access? To what system and organizational resources should access be allowed? What types of access should each user be allowed for each resource?

Security Planning - Policy What are the organization’s goals on security? Where does the responsibility for security lie? What is the organization’s commitment to security?

OCTAVE Methodology http://www.cert.org/octave/ Identify enterprise knowledge. Identify operational area knowledge. Identify staff knowledge. Establish security requirements. Map high-priority information assests to information infrastructure. Perform an infrastructure vulnerability evaluation. Conduct a multidimensional risk analysis. Develop a protection strategy.

Security Planning – Requirements of the TCSEC Security Policy – must be an explicit and well-defined security policy enforced by the system. Every subject must be uniquely and convincingly identified. Every object must be associated with a label that indicates its security level. The system must maintain complete, secure records of actions that affect security. The computing system must contain mechanisms that enforce security. The mechanisms that implement security must be protected against unauthorized change.

Security Planning Team Members Computer hardware group System administrators Systems programmers Application programmers Data entry personnel Physical security personnel Representative users

Security Planning Assuring Commitment to a Security Plan Business Continuity Plans Assess Business Impact Develop Strategy Develop Plan Incident Response Plans Advance Planning Response Team After the Incident is Resolved

Risk Analysis Risk impact - loss associated with an event risk probability – likelihood that the event will occur Risk control – degree to which we can change the outcome Risk exposure – risk impact * risk probability

Risk Analysis – risk reduction Avoid the risk Transfer the risk Assume the risk Risk leverage = [(risk exposure before reduction) – (risk exposure after reduction)] / cost of risk reduction Cannot guarantee systems are risk free Security plans must address action needed should an unexpected risk becomes a problem

Steps of a Risk Analysis Identify assets Determine vulnerabilities Estimate likelihood of exploitation Compute expected annual loss Survey applicable controls and their costs Project annual savings of control

Identify Assets Hardware Software Data People Procedures (policies, training) Documentation Supplies Infrastructure (building, power, water,…)

Determine Vulnerabilities Asset Confidentiality Integrity Availability Hardware Software Data People procedures

Determine Vulnerabilities What are the effects of unintentional errors? What are the effects of willfully malicious insiders? What are the effects of outsiders? What are the effects of natural and physical disasters?

Risk Analysis Estimate Likelihood of Exploitation Classical probability Frequency probability (simulation) Subjective probability (Delphi approach) Computer Expected Lost (look for hidden costs) Legal obligations Side effects Psychological effects

Risk Analysis Survey and Select New Controls Project Savings What Criteria Are Used for Selecting Controls? Vulnerability Assessment and Mitigation (VAM) Methodology How Do Controls Affect What They Control? Which Controls Are Best? Project Savings Do costs outweigh benefits of preventing / mitigating risks

Arguments for Risk Analysis Improve awareness Relate security mission to management objectives Identify assets, vulnerabilities, and controls Improve basis for decisions Justify expenditures for security

Arguments against Risk Analysis False sense of precision and confidence Hard to perform Immutability (filed and forgotten) Lack of accuracy “Today’s complex Internet networks cannot be made watertight…. A system administrator has to get everything right all the time; a hacker only has to find one small hole. A sysadmin has to be lucky all of the time; a hacker only has to get lucky once. It is easier to destroy than to create.” Robert Graham, lead architect of Internet Security Systems

Organizational Security Policies Who can access which resources in what manner? Security policy - high-level management document that informs all users of the goals and constraints on using a system.

Security Policies Purpose Recognize sensitive information assets Clarify security responsibilities Promote awareness for existing employees Guide new employees

Security Policies Audience Users Owners Beneficiaries Balance Among All Parties

Contents Purpose Protected Resources (what - asset list) Nature of the Protection (who and how)

Characteristics of a Good Security Policy Coverage (comprehensive) Durability Realism Usefulness

Physical Security Natural Disasters Power Loss Human Vandals Flood Fire Other Power Loss UPS; surge suppressors (line conditioners) Human Vandals Unauthorized Access and Use Theft

Physical Security Interception of Sensitive Information Dumpster Diving - Shredding Remanence (slack bits) Overwriting Magnetic Data DiskWipe Degaussing Emanation - Tempest

Contingency Planning BACKUP!!!!! OFFSITE BACKUP!!!!! Complete backup Revolving backup Selective backup OFFSITE BACKUP!!!!! Networked Storage (SAN) Cold site (shell) Hot site

A cold site is a facility with power and cooling available, in which a computing system can be installed to begin immediate operation. A hot Site is a computer facility with an installed and ready-to run computing system.