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UK ATM fraud in the 1990s

The Register: How ATM fraud nearly brought down British banking. This story is mind-boggling; it claims that UK ATM security had two major issues that have been kept secret since the 1990s:

  • An insecure data format used for the data on the magnetic stripes in one bank’s cards;

  • Another bank’s computing department “going rogue”, “cracking PINs and taking money from customers’ accounts with abandon” as the story puts it. Yikes.

The latter problem is scary, but in my opinion the former problem is more interesting from a computer security point of view.

This is a classic example of bad data format design, as it left the PIN and the account details individually rewritable — in other words, an attacker could (and did) change one while keeping the other intact.

This British Computer Society abstract provides more details on the who, how and where:

… it was revealed that UKP 130,000 had been stolen from Abbey National cardholders during 1994 and 1995 with counterfeit cards. Andrew Stone, a bank security consultant who had been advising Which?, the magazine of the Consumers’ Association, was jailed for five and a half years for the theft. This fraud involved spying on Abbey customers as they used their cards in automated teller machines (ATMs) or cash dispensers… [Stone] recorded card details and personal identification numbers (PINs) using powerful video cameras. The details were then encoded on the magnetic strips of other cards.

Finally, another quote from the Reg story:

why is he telling this explosive story now? Because chip and PIN has been deployed across the UK ATM network. “The vulnerability in the UK ATM network was still there to be exploited — if someone had chanced upon it.”

I wonder if other banking systems worldwide are still vulnerable, however? Did any other banks elsewhere license the vulnerable systems from UK banks, without knowing about these vulnerabilities? How long did it take for them to be fixed, if they were fixed?

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