/aug 15, 2008

MBTA Hack: Is It Really This Easy?

By Chris Wysopal

A lot of the focus of the MBTA vs MIT case has been discussion of the CharlieCards. These are MiFare classic cards which have been known to be broken earlier this year. There is also a paper disposable card called the CharlieTicket that uses a magnetic stripe. The MIT students presentation states that these are cloneable and forgeable using a $150 magnetic stripe reader/writer. From the Confidential Memo Prepared for the MBTA
which was publicly disclosed by the MBTA is court filing:

This seems to break all the rules of integrity of sensitive data storage. How could someone store money on a magnetic stripe in 2008 and not store an identifier that references the account in a central database?

The tickets do have a unique identifier generated when the card is initially purchased so a fraud detection system could be in place or is planned. But this would require tracking the value on the ticket or the usage of the ticket centrally so it isn't clear why the value is stored on the card in the first place.

There are so many question about the security of this public system. Fraud costs the Massachusetts taxpayer money and refitting an insecure, ill-designed system costs the Massachusetts taxpayer money. [Disclosure: I am a Massachusetts taxpayer.]

It should be a requirement that the current system or the (hopefully) upgraded system be tested by an independent organization that specializes in cryptosystems. If the independent testing uncovers vulnerabilities, they need to be fixed before the system is fielded. Then the system should be retested to verify the fixes. Once the system is deemed secure by an independent organization, a summary of the test document should be published for public inspection. It should include the types of testing conducted and the results.

The public trust requires inspection of taxpayer funded projects to make sure they meet acceptible standards and vendors held responsible for deficiencies. Projects that use computers and software should not get a free pass. It will be interesting to see if the CharlieTicket system is ever held up to public scrutiny.

Veracode Security Solutions
Veracode Security Threat Guides

Related Posts

By Chris Wysopal

Chris Wysopal, co-founder and CTO of Veracode, is recognized as an expert and a well-known speaker in the information security field. He has given keynotes at computer security events and has testified on Capitol Hill on the subjects of government computer security and how vulnerabilities are discovered in software. His opinions on Internet security are highly sought after and most major print and media outlets have featured stories on Mr. Wysopal and his work. At Veracode, Mr. Wysopal is responsible for the security analysis capabilities of Veracode technology.