Nipponica

Certain chips shipped before 2017 are vulnerable, Sony said, acknowledging the issue after inquiries from Kyodo News. Over 1.8 billion FeliCa chips have been produced so far, powering transit cards as well as employee and student identification cards.

Cybersecurity experts warn attackers could alter transit cards, disrupt electronic payments or forge passes for sensitive facilities, with one analyst describing it as an "extremely serious" problem that undermines trust in infrastructure.

While it is good that the cards that have this flaw are almost a decade old, it is still a big vulnerability. The move to digital cards and (unfortunately) QR codes is pressing forward, but FeliCa is still the core of the Japan transit network.