Bank Card "Master Key" Stolen

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/06/bank_card_maste.html

South Africa’s Postbank experienced a catastrophic security failure. The bank’s master PIN key was stolen, forcing it to cancel and replace 12 million bank cards.

The breach resulted from the printing of the bank’s encrypted master key in plain, unencrypted digital language at the Postbank’s old data centre in the Pretoria city centre.

According to a number of internal Postbank reports, which the Sunday Times obtained, the master key was then stolen by employees.

One of the reports said that the cards would cost about R1bn to replace. The master key, a 36-digit code, allows anyone who has it to gain unfettered access to the bank’s systems, and allows them to read and rewrite account balances, and change information and data on any of the bank’s 12-million cards.

The bank lost $3.2 million in fraudulent transactions before the theft was discovered. Replacing all the cards will cost an estimated $58 million.