security planning susan lincke designing information security

Security PlanningSusan Lincke

Designing Information Security

Security Planning: An Applied Approach | 04/19/23 | 2

ObjectivesStudent should know:

Define information security principles: need-to-know, least privilege, segregation of duties, privacy

Define information security management positions: data owner, data custodians, security administrator

Define access control techniques: mandatory, discretionary, role-based, physical, single sign-on

Define authentication combination: single factor, two factor, three factor multifactor

Define Biometric: FRR, FAR, FER, EER

Define elements of BLP: read down, write up, tranquility principle, declassification

Define military security policy: level of trust, confidentiality principle

Define backup rotation, incremental backup, differential backup, degauss, audit trail, audit reduction, criticality classification, sensitivity classification

Develop an information security classification scheme that addresses confidentiality and availability


Information Security Goals

CIA Triad

Confidentiality

Integrity Availability

Conformity to Law& Privacy Requirements


Information Security Principles

Need-to-know: Persons should have ability to access data sufficient to perform primary job and no moreLeast Privilege: Persons should have ability to do tasks sufficient to perform primary job and no moreSegregation of Duties: Ensure that no person can assume two roles: Origination, Authorization, Distribution, VerificationPrivacy: Personal/private info is retained only when a true business need exists: Privacy is a liabilityRetain records for short timePersonnel office should change permissions as jobs change


Review: State Breach Law Protects…

Restricted data generally includes:Social Security NumberDriver’s license # or state ID #Financial account number (credit/debit) and access code/passwordDNA profile (Statute 939.74)Biometric dataSome states & HIPAA protects:Health status, treatment, or payment


President

BusinessExecutive

Chief Privacy OfficerProtect

customer & employee rights

Chief InfoSec. OfficerCreates andmaintains a sec. program

Data OwnerResponsible for

security ofdata

Chief Sec. OfficerPhysical Security

Security ArchitectDesign/ impl.

policies &procedures

Security Admin

Administrates computer &

network security

Process Owner

Responsible forsecurity of

process

IS AuditorIndependentassurance of

sec. objectives& controls

Some positions may be merged

DataCustodianMaintains and protects data:

Backup/restore/monitor/test

Chief Info. OfficerManages

Info. Technology


Information Owneror Data OwnerIs responsible for the data within business (mgr/director - not IS staff)Determines who can have access to data and may grant permissions directly ORGives written permission for access directly to security administrator, to prevent mishandling or alterationPeriodically reviews authorization to restrict authorization creep


Other Positions

Data CustodianIS (security or IT) employee who safeguards the dataPerforms backup/restoreVerifies integrity of dataDocuments activitiesMay be System Administrator

Security AdministratorAllocates access to employees based on written documentationMonitors access to terminals and applications• Monitors invalid login attemptsPrepares security reports


Criticality Classification

Critical $$$$: Cannot be performed manually. Tolerance to interruption is very low

Vital $$: Can be performed manually for very short time

Sensitive $: Can be performed manually for a period of time, but may cost more in staff

Nonsensitive ¢: Can be performed manually for an extended period of time with little additional cost and minimal recovery effort


Sensitivity Classification(Example)

Proprietary:Strategic Plan

Confidential:Salary &

Health Info

Private:Product Plans

PublicProduct Users Manual

near Release

Internal


Sensitivity ClassificationWorkbook

SensitivityClassification

Description Information Covered

Proprietary Protects competitive edge. Material is of critical strategic importance to the company. Dissemination could result in serious financial impact.

Confidential Information protected by FERPA, PCI-DSS and breach notification law. Shall be available on a need-to-know basis only. Dissemination could result in financial liability or reputation loss.

Student information & grades,

Payment card information,Employee information

Private Should be accessible to management or for use with specific parties. Could cause internal strife or divulge trade secrets if released.

Professor research, Student homework,

Budgets

Public Disclosure is not welcome, but would not adversely impact the organization

Teaching lectures


Data Classification

How do we mark classified information?How do we determine which data should be classified to which class?How do we store, transport, handle, archive classified information?How do we dispose of classified data?What does the law say about handling this information?Who has authority to determine who gets access, and what approvals are needed for access?


Handling of Sensitive Data

Confidential Private PublicAccess Need to know Need to know Need to knowPaper Storage Locked cabinet,

Locked room if unattended

Locked cabinet


Locked cabinet or locked room if unattended

Disk Storage Password-protected,

Encrypted

Password-protected

Encrypted

Password-Protected

Labeling & Handling

Clean desk, low voice,

No SSNs, ID required

Clean desk,

low voice

Clean desk,

low voiceTransmission Encrypted

Limited email or append email security notice

Encrypted

Archive Encrypted EncryptedDisposal Degauss & damage disks

Shred paper

Secure wipe

Shred paper

Reformat disks


Storage & Destruction of Confidential Information

StorageEncrypt sensitive dataAvoid touching media surfaceKeep out of direct sunlightKeep free of dust & liquids – in firm container bestAvoid magnetic, radio, or vibrating fieldsUse anti-static bags for disksAvoid spikes in temperature for disks; bring to room temperature before useWrite protect floppies/magnetic mediaStore tapes vertically

Disposing of MediaMeet record-retention schedulesReformat diskUse “Secure wipe” tool****If highly secure*****Degauss = demagnetize Physical destruction

RepairRemove memory before sending out for repair


Permission types

Read, inquiry, copyCreate, write, update, append, deleteExecute, check

Access Matrix Model (HRU)

File A File B File C Jack

Jack rwx rx -

Jill rwx r d

Jeff r rx rwx -


Information Asset Inventory Asset Name Course Registration

Value to Organization Records which students are taking which classes

Location IS Main Center

Sensitivity & CriticalityClassifications

Sensitive, Vital

IS System/Server Name

Peoplesoft

Data Owner Registrar: Monica Jones

DesignatedCustodian

IS Operations: John Johnson

Granted Permissions Read: Department Staff, AdvisingRead/Write: Students, Registration

Access is permitted at any time/any terminal

CISA Review Manual 2009

Workbook


Question

The person responsible for deciding who should have access to a data file is:

1. Data custodian2. Data owner3. Security administrator4. Security manager


Question

Least Privilege dictates that:1. Persons should have the ability to do tasks sufficient to

perform their primary job and no more2. Access rights and permissions shall be commensurate with a

person’s position in the corporation: i.e., lower layers have fewer rights

3. Computer users should never have administrator passwords4. Persons should have access permissions only for their security

level: Confidential, Private or Sensitive


Question

A concern with personal or private information is that:1. Data is not kept longer than absolutely necessary2. Data encryption makes the retention of personal information

safe3. Private information on disk should never be taken off-site 4. Personal data is always labeled and handled as critical or vital

to the organization


Question

The person responsible for restricting and monitoring permissions is the:

1. Data custodian2. Data owner3. Security administrator4. Security manager


AUTHENTICATION & ACCESS CONTROL

Path AccessAuthentication: Login/Password, BiometricsRemote Access


Security: Defense in Depth

Border RouterPerimeter firewallInternal firewallIntrusion Detection SystemPolicies & Procedures & AuditsAuthenticationAccess Controls


Four Layers of Logical Security

DatabaseApp1

App2

System 1 System 2

Two layers of general access to Networks and SystemsTwo layers of granularity of control to Applications and Databases


Password Rules

One-way encrypted using a strong algorithmNever displayed (except ***)Never written down and retained near terminal or in deskPasswords should be changed every 30 days, by notifying user in advanceA history of passwords should prevent user from using same password in 1 yearPasswords should be >= 8 (better 12) characters, including 3 of: alpha, numeric, upper/lower case, and special charactersPasswords should not be identifiable with user, e.g., family member or pet name


Authentication Combinations

Single Factor: Something you know• Login & PasswordMultifactor Authentication: Using two or more authentication methods. Two Factor: Add one of:• Something you have: Card or ID• Something you are or do: BiometricThree Factor: Uses all three: e.g., badge, thumb, pass code


Biometrics

Biometrics: Who you are or what you doSusceptible to errorFalse Rejection Rate (FRR): Rate of users rejected in errorFalse Acceptance Rate (FAR): Rate of users accepted in errorFailure to Enroll Rate (FER): Rate of users who failed to successfully register

Equal Error Rate EER:

FRR = FARFAR increasesFRR increases


Biometrics with Best Response & Lowest EER

Type (Top Best) Advantages Disadvantages

Palm Social acceptance Physical contact

Hand (3D) Social acceptance, low storage Not unique, injury affects

Iris No direct contact High cost, high storage

Retina Low FAR High cost, 1-2 cm away: invasive

Fingerprint Low cost, More storage=Lower EER

Physical contact-> grime ->poor quality image

Voice Phone use, social acceptance High storage, playback, voice change, background noise

Signature Easy to use, low cost Uniqueness, writing onto tablet differs from paper

Face Social acceptance Not unique, overcome with high storage



Biometric Info Mgmt & Security Policy

Identification & authentication proceduresBackup authenticationSafe transmission/storage of biometric dataSecurity of physical hardwareValidation testingAuditors should ensure documentation & use is professional


Single Sign OnAdvantages

One good password replaces lots of passwords

IDs consistent throughout system(s)

Reduced admin work in setup & forgotten passwords

Quick access to systems

Disadvantages

Single point of failure -> total compromise

Complex software development due to diverse OS

Expensive implementation

Secondary Domains

App1 DB2 App3

Primary Domain (System)

Enter Password


Recommended Password Allocation

User allocatedrandom password

or sent email w. link

First time login:change

password

UserSecurity Admin

Verify user ID(e.g., email)

NotifySecurity

Inform user in controlled

manner

[Forgot Password]

Enter 5 invalidpasswords

Account[locked]

[Invalid passwordAttempts]

System automatically

unlocks

[Auto Timeout]

Account[unlocked]

Account[unlocked]

[Manual]

SubsequentLogins


Admin & Login ID Rules

Restrict number of admin accountsAdmin password should only be known by one userAdmin accounts should never be locked out, whereas others areAdmin password can be kept in locked cabinet in sealed envelope, where top manager has keyLogin IDs should follow a confidential internal naming ruleCommon accounts: Guest, Administrator, Admin should be renamedSession time out should require password re-entry


Access Control Techniques

Mandatory Access Control Discretionary Access Control

File User Group Permi…A John Mgmt rwx, r xB June Billing , r C May Factory r x, r xD Al BillingE Don Billing

Role-Based Access Control

Login Role PermissionJohn Mgr A, B,C,D,E,FJune Acct. A,B,CAl Acct. A,B,CMay Factory D,E,FPat Factory D,E,F

JohnA, B, C, D, E, F

JuneA, B, C

MayD, E, F

AlA, B

DonB, C

PatD, F

TomE, F

TimE


Access Control Techniques

Mandatory Access Control: General (system-determined) access control

Discretionary Access Control: Person with permissions controls access

Role-Based Access Control: Access control determined by role in organization

Physical Access Control: Locks, fences, biometrics, badges, keys


Workbook:Role-Based Access Control

Role Name Information Access (e.g., Record or Form) andPermissions (e.g., RWX)

Instructor Student Records: Grading Form RW Student Transcript (current students) R Transfer credit form R

Advising Student Records: Student Transcript (current students) R Fee Payment R Transfer credit form R

Registration Student Records: Fee Payment RW Transfer credit form RW


System Access Control

Establish rules for access to information resourcesCreate/maintain user profilesAllocate user IDs requiring authentication (per person, not group)Notify users of valid use and access before and upon loginEnsure accountability and auditability by logging user activitiesLog eventsReport access control configuration & logs


Application-Level Access ControlCreate/change file or database structureAuthorize actions at the:• Application level• File level• Transaction level• Field levelLog network & data access activities to monitor access violations


Which Computer Do You Trust?

You plan to make a purchase on-line…

Your office computer?A library or college computer?

Your children’s computer?


Trusted Computing Base (TCB)

Trusted Hardware

Trusted Operating System

TrustedApp 1

TrustedApp 2

Trusted

App 3

Trusted Hardware

Trusted Operating System

TrustedService

1

TrustedService

2

Trusted

Service 3

Trusted network

Trusted app hasHorizontal dependencies: operating system, hardwareVertical dependencies: server applications, network, authentication server, …


Processing requires Dependencies

Vertical Dependencies:Secret App requiresSecret-level databaseSecret-level OSSecret-level hardware

Horizontal Dependencies:Secret App requires:Secret-level serversSecret-level communicationsSecret-level authentication


Trusted Computing Base (TCB)

Trusted Hardware

Trusted OS

TrustedApp 1

TrustedApp 2

TrustedApp 3

Trusted Hardware

TrustedOS

TrustedService

1

TrustedService

2

TrustedService

3

Trusted network

Security Policy

Encapsulated security impl.

Encapsulated security impl.

TCB Subset: Verified security policy, provides reliabilityEncapsulated security implementation provides rapid implementation


Bell and La Padula Model (BLP)

Property of Confinement:

Read Down: if Subject’s class is >= Object’s class

Write Up: if Subject’s class is <= Object’s class

Tranquility Principle: Object’s class cannot change

Declassification: Subject can lower his/her own class

Top Secret

Secret

Confidential

Non-Classified

write

read

& write

read

read

Joe => (Secret)


Military Security Policy

Person has an Authorization Level or Level of Trust(S,D) = (sensitivity, domain) for Subject (potentially Project)Object has a Security ClassConfidentiality Property: Subject can access object if it dominates the object’s classification level

Class Finance Engineering Personnel

Top Secret Customer list New plans

Secret Dept. Budgets Code Personnel review

Confidential Expenses Emails Salary

Non-Classified Balance sheet Users Manuals

Position Descriptions

(Secret, Eng)(Confid., Finance)


BIG Data

Alice Winter 222 Pine Dr. 262-513-2341 Birth=1989 Diabetic

Options include:Encryption, access control, firewall, security intelligenceObfuscate: Make data unclearDistribute data across multiple locationsNo single location has useful data (e.g., RAID)

Blacklist: Not storedOr access via permission

Anonomize: Alter via statistical distribution

Whitelist: Permitted to see


IS Auditor Verifies…

Written Policies & Procedures are professional & implementedAccess follows need-to-knowSecurity awareness & training implementedData owners & data custodians meet responsibility for safeguarding dataSecurity Administrator provides physical and logical security for IS program, data, and equipmentAuthorization is documented and consistent with realitySee CISA Review Manual for specific details


Question

A form of biometrics that is considered invasive by users is:1. Retina2. Iris3. 3D hand4. Signature


Question

A form of biometrics that is not prone to error is1. Retina2. Voice3. Finger4. Signature


Question

Julie is a Data Owner. She configures permissions in the database to enable users to access the forms she thinks they should be able to access. This technique is known as

1.Bell and La Padula Model

2.Mandatory Access Control

3.Role-Based Access Control

4.Discretionary Access Control



Question

John has a security clearance of (Engineering, Confidential). Using Bell and La Padula Model, John can write to:

1.Confidential

2.Top Secret, Secret, and Confidential

3.Confidential and Unclassified

4.Unclassified



AUDIT TRAILS


Audit Trail

Audit trail tracks responsibility• Who did what when?• Periodic review will help to find excess-authority access, login successes &

failures, and track fraud

Attackers often want to change the audit trail (to hide tracks)Audit trail must be hard to change:• Write-once devices• Digital signatures• Security & systems admins and managers may have READ-only access to log

Audit trail must be sensitive to privacy• Personal information may be encrypted


Audit Trail Tools

Audit Reduction: Filter important logs - eliminate unimportant logs

Attack/Signature Detection: A sequence of log events may signal an attack (e.g., 1000 login attempts)

Trend/ Variance-Detection: Notices changes from normal user or system behavior (e.g., login during night)


Question

Audit trails:1. Should be modifiable only by security administrators2. Should be difficult to change (e.g., write-once)3. Should only save important logs, using log reduction4. Should avoid encryption to ensure no loss and quick

access


Data in inventoried

Data is allocated a sensitivity and criticality class

Class handling is defined for handling, transporting, storage

Roles are allocated permissions (access control)

Authorization ensures access control is enforced: biometrics, two-factor authentication, single sign-on

Trust enables use

Access may be distributed: Trusted Computing Base

Audit trails enforce accountability

Summary


HEALTH FIRST CASE STUDY

Designing Information Security

Jamie Ramon MDDoctor

Chris Ramon RDDietician

TerryLicensed

Practicing Nurse

PatSoftware Consultant


Define Sensitivity Classification

Sensitivity

Classification

Description Information Covered

Proprietary Protects competitive edge. Material is of critical strategic importance to the company and its dissemination could result in serious financial impact.

Confidential Information protected by law. Shall be made available or visible on a need-to-know basis only. Dissemination could result in financial liability or reputation loss.

Private Should be accessible to management or affected parties only. Could cause internal strife or external embarrassment if released: for use with particular parties within the organization.

Public Disclosure is not welcome, but would not adversely impact the organization

OR

Information is public record


Define Sensitivity Classification

Medical appointments

Credit card information

Budget

Personnel records

Patient treatmentContracts & Licenses

Business

Statistics


How should classes be treated?Table 4.1.2: Handling of Sensitive Data

Proprietary Confidential PrivateAccess Need to know Need to know Need to knowPaper Storage Locked cabinet,


Locked cabinetLocked room if unattended

Locked cabinet or locked room if unattended

Disk Storage Password-protected,Encrypted

Password-protectedEncrypted

Password-Protected

Labeling and Handling

‘Confidential’Clean desk, low voice,shut door policy

Clean desk,low voice,shut door policy

Clean desk,low voice,shut door policy

Transmission Encrypted Encrypted Archive Encrypted Encrypted Disposal Degauss & damage disks

Shred paperSecure wipe, damage disksShred paper

Reformat disks

Special


Define Roles & Role-Based Access Control

Role Name Information Access (e.g., Record or Form)

and Permissions (e.g., RWX)

Health Plan EligibilityHealth Plan: Eligibility: ActiveMaximum Benefit: Co-Pay: Deductible:ExclusionsIn-Plan Benefits Out-of-Plan Benefits Coordination of Benefits

Specific Procedure RequestProcedure Coverage Max. Coverage Co-pay / Non-coveredDates Patient Resp Amounts


Information Asset Inventory Asset Name Course Registration

Value to Organization

Records which students are taking which classes

Location IS Main Center

Security Risk Classification

Sensitive, Vital

IS Server Peoplesoft

Data Owner (Who decides who should have access?)

Designated Custodian

(Who takes care of backups and sys admin functions?)

Granted Permissions Read: Department Staff, AdvisingRead/Write: Students, Registration

Access is permitted at any time/any terminal

Workbook