Smart Cards By Simon Siu and Russell Doyle

Overview Size of a credit card Small embedded computer chip – Memory cards – Processor cards – Electronic purse cards (FSU ID card) – Security cards Processor cards require a reader

History of Smart cards Patented in 1970s (several different designs) 1983: first mass use in France for pay phone 1992: second mass use again in France for debit cards 1993: Visa, MasterCard, Europay agreed on a standard (EMV) Contactless technology is the new trend

Hardware: Chip is accessed electronically via gold plate

Smart card vs. Magnetic strip card Smart card is more secure – Data encryption ability – Difficult to access data without terminal Smart card is more expensive Smart card is less durable

Usage Banking – ATM Payment – Like credit card Access control – Certificate holder (able to do triple DES) Id Information storage

Prime examples Medical application: Germany issues smart cards to all citizens India driver’s licenses (becoming popular in other countries) China transit (GuongZhou) England tracking device in airports

Programming the Card OpenCard – Java interface, Java Electronic Commerce Framework (JECF) PC/SC – Window’s based interface

Modeling Security Threats Breaking Up Is Hard To Do: Modeling Security Threats for Smart Cards by Schneier and Shostack

Smart Card ’ s handicap Functionality is split in unusual ways compare to a computer Unable to interact with the world without outside peripherals Multiple parties

Cardholder Holding the card May or may not control the info in card Does not control the protocols, software, or hardware in the card system

Data Owner May or may not control data in the card Digital certificates Amount of money in account

Terminal Control all I/O to and from the card Phone ATM Set-top box

Card Issuer Control operating system running on the card Initial data Card manufacturer Software manufacturer

Examples of Trust Splits in Smart card systems Digital Stored Value Card – Cash card – Mondex – VisaCash Digital Check Card – Similar to cash card – Card owner is also the data owner Prepaid Phone Card – Value card Account-based Phone Card – Account number

Continues Access Token – Key to login or authenticatio protocol Web Browsing Card – Cash card – Cardholder and terminal owner are the same

Continues Digital Credential Device – Digital certificates or ther credentials – Cardholder and data owner are the same – Kerberos – DSSA/SPX Key Storage Card – Key Multi-Function Card

Threats Attack is an attempte by one or more parties involved in a smart card transaction to cheat Interfere with one or more parties Inside vs Outside Attacks – One of the parties – Outsider stealing a card

Motives for Attack Financial theft Impersonation attack: gain access Privacy attack Publicity attack

Classes of Attack Attack by the Terminal against the cardholder or data owner – Fake ATM machines – Assume we trust the terminal – Preventions Limit the time to modify Limit the amount of $ reduced at a given time Real prevention is monitering by back-end system

Continues Attack by the cardholder against the terminal – Fake cards with rogue software – Preventions Good protocol design Hard-to-forge physical aspects –Hologram on Visa

Continues Attack by the cardholder against the data owner – Pay-TV access cards – Reverse-engineering – Defeat tamper-resistance – Fault analysis Attack by the cardholder against the issuer – Randomly access an acount with account-based phone cards – If there is a key, capture the key and use it

Continues Attack by the cardholder against the software manufacturer – One application on a smard card to subvert another running on the same card.

Conclusion on Security Resistance – Make specific attacks harder: stronger cryptographic protocols, increase tamper-resistance – Few splits to eliminate certain attacks altogeter Example cardholder is also the data owner which means no cardholder attacking data owner – Adding screen and data entry to the card Increase the cost – More Transparency Open publication leads to review and analysis Cleanly separating roles –Example Mondex system with various terminals –User can check his/her account in any one of them

Evolution of Smart cards or lack there of Why is it not popular in America yet? – Social environment Split government systems Class differences Market forces – Cost vs. Benefit

Future of smart cards Security of smart card is similar with the security of PC New technology help to further secure smart system – Digital display on the card Contact vs. Contactless

References threats.pdf threats.pdf