How to Evaluate Data Protection Technologies

Ulf Mattsson, CTO, Protegrity Corporation

Payment System Integrity

Protecting Data in the Enterprise Data Flow

• ‘Information in the wild’- Short lifecycle / High risk

• Temporary information - Short lifecycle / High risk

• Operating information- Typically 1 or more year lifecycle- Broad and diverse computing and database environment

• Decision making information- Typically multi-year lifecycle- Homogeneous computing environment- High volume database analysis

• Archive -Typically multi-year lifecycle -Preserving the ability to retrieve the data in the future is important

POS e-commerce Branch

Aggregation

Operations

Analysis

Archive

Collection

Payment System Integrity

PCI Case Study – Large Retailer

• Minimal impact to the legacy environment– Encrypting PAN in the POS application and decrypting in HQ

server

– Encrypting PAN in databases, transparent to applications

– Software encryption – 10 million transactions per second

• End-to-end encryption within the control of a single enterprise– Modifications of applications, files and databases

– Definition of “Strong cryptography” - PCI DSS Glossary 1.2

– Central management of encryption keys, policy and reporting

– Key Management - Industry Standards are missing (IEEE P1619.3, OASIS/KMIP …)

03

Payment System Integrity 4

End-to-end Encryption - Challenges

• End-to-end encryption in the financial environment– End-to-end encryption is a very difficult thing to accomplish in the financial

environment

– The people and devices at one end do not usually have any relationship (such as shared keys) with those at the other end - things are more point-to-point

– Expanding the scope - flow through the existing payment networks and not break them

– Or change all those networks (not easy!) or provide a separate path for messages using a new scheme

– OASIS/KMIP Key Management is immature in the area of support for banking and finance requirements

– Some vendors add proprietary encryption capability to the terminals themselves

Payment System Integrity 5

Planned Proposal to X9 for New Standard

• Current scope - client-end-terminal to acquirer

– It's not quite clear what direction this will end up taking

– Encryption/decryption to be done in software for performance reasons

• X9 ANSI Standard may be published within 36-40 months

– ASC X9 working group - one initial meeting so far

– More time for people to actually implement it

• Target audience for this guideline or standard

– POS Device Implementers, ATM Implementers, Store Controller Implementers, Retail Host System Implementers, Processing System Implementers and Acquiring System Implementers

Payment System Integrity 6

Protecting Data in the Enterprise Data Flow

Database Server

Database Activity Monitoring /

Data Loss Prevention

Web Application Firewall

TablespaceDatafiles

Database Log Files

Applications

DatabaseColumns

Database Activity

Monitoring

Passive ApproachesActive ApproachesPassive Approaches and Active Approaches = End-To-End Protection

Payment System Integrity 7

Passive Data Protection Approaches

• Web Application Firewall– Protects against malicious attacks by inspecting application

traffic• Data Loss Prevention

– Tags and monitors movement of sensitive assets– Protects against the unintentional outbound leakage of

sensitive assets• Database Activity Monitoring

– Inspects , monitors, and reports database traffic into and out of databases

– Can block malicious activity; seldom used due to false positives

• Database Log Mining– Mines log files that are created by databases for good or bad

activity

Payment System Integrity 8

Active Data Protection Approaches

• Application Protection

– Utilizes crypto APIs to protect sensitive assets in applications

– This approach helps you protect data as it enters your business systems

• Column Level Protection

– Protects data inside the database at the column level

– Can be deployed in a transparent approach to minimizes changes to your environment

– Considered to be the most secure approach to protect sensitive assets

• Database file protection

– Protects the data by encrypting the entire database file

Payment System Integrity 9

Passive Database Protection Approaches

Database Protection Approach

Performance Storage Security Transparency Separation of Duties

Web Application Firewall

Data Loss Prevention

Database Activity Monitoring

Database Log Mining

Best Worst

Operational Impact Profile

Payment System Integrity 10

Active Database Protection Approaches

Database Protection Approach

Performance Storage Security Transparency Separation of Duties

Application Protection - API

Column Level Encryption; FCE, AES, 3DES

Column Level Replacement; Tokens

Tablespace - Datafile Protection

Best Worst

Operational Impact Profile

Payment System Integrity 11

How about Native Database Encryption?

• Advantages

– Available from most database vendors

– Enables you to get started quickly

• Disadvantages

– Mostly non-transparent solutions

– Some vendors do not protect the Data Encryption Keys well enough

– Lack of secure interoperability between instances of the same vendor

– No secure interoperability with databases from other vendors

– No centralization of policy, key management, and audit reporting

Payment System Integrity 12

WebApps

Polling Server

Partners(Financial

Institutions)

Archive

HQ

Branches/Stores

Store Back OfficePoints of collection

T-Logs,Journals

Store Back Office

Applications

StoreDB

RetailLocales

Multiplexing Platform

ERP

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Manager

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Policy

Policy

Policy

Policy

Policy

Policy

Log

Log Log

Log

Reports

Collection

Aggregation

Operations

Tactical

Detailed Analytical

Focused / Summary Analytical

Active Access / Alerting

Analytics

Security for the Sensitive Data Flow

Payment System Integrity 13

Data Protection Options and Formats

• Clear – actual value is readable – not for cardholder data

• Hash – unreadable, not reversible – not for cardholder data

• Encrypted – unreadable, reversible

• Replacement value (tokens) – unreadable, reversible

• Partial encryption/replacement – unreadable, reversible

Payment System Integrity 14

Data in the Clear

• Description

– Audit only

– Masking

– Access Control Limits

• Advantages

– Low impact on existing applications

– Performance and time to deploy

• Considerations

– Underlying data exposed

Payment System Integrity 15

Strong Encryption

• Description

– Industry standard (AES CBC …)

• Advantages

– Widely deployed

– Compatibility

– Performance

• Considerations

– Storage and type

– Transparency to applications

– Key rotation

Payment System Integrity 16

Format Controlling Encryption

• Description– Maintains data type, length

• Advantages– Reduces changes to downstream systems– Storage– Partial encryption

• Considerations– Performance– Security and key rotation– Transparency to applications

Payment System Integrity 17

Replacement Value (i.e. tokens, alias)

• Description

– Proxy value created to replace original data

– Centrally managed, protected

• Advantages

– No changes to most downstream systems

– Out of scope for compliance

– No local key rotation

• Considerations

– Transparency for applications needing original data

– Availability and performance for applications needing original data

Payment System Integrity

“Strong cryptography” - PCI DSS Glossary 1.2

• Examples - AES (128 bits and higher) and TDES

– Payment Card Industry (PCI) Data Security Standard (DSS)

– Payment Application Data Security Standard (PA-DSS)

• NIST Special Publication 800-57

– Five confidentiality modes (ECB, CBC, OFB, CFB, and CTR)

– One authentication mode (CMAC)

– Two combined modes for confidentiality and authentication (CCM and GCM)

• Some New Encryption Modes of operation that NIST is considering

– FFSEM, Feistel Finite Set Encryption Mode (Posted February, 2008) 9-16 digits

– ABC, Accumulated Block Chaining (Posted October, 2000)

Payment System Integrity 19

Data Protection Capabilities

Storage Performance Storage Security Transparency

Clear

Strong Encryption

Format Controlling Encryption

Token

Hash

Best Worst

Payment System Integrity 20

Data Protection Implementation Choices

• Data Protection Layers

– Application

– Database

– File System

• Data Protection Topologies

– Remote or local service

• Data Security Management

– Central management of keys, policy and reporting

Payment System Integrity 21

Topology Performance Scalability Security

Local Service

Remote Service

Data Protection Implementation Choices

System Layer Performance Transparency Security

Application

Database

File System

Best Worst

Payment System Integrity 22

Data Protection Strategies

• Where to start?

– “Perimeter towards Database” Strategy

– “Database towards Perimeter” Strategy

– Combined Strategy

• Use risk based methodology to determine how to protect sensitive assets

– Value of your data X Exposure = Risk

– Apply the appropriate approach based on risk

• Choose a protection vendor with

– Broad coverage of protection options

– Central policy, key, and audit management

– Ability to protect across a wide range of database platforms