3 ms·
> Surely you can just run the card through a reader before and after taking some journeys and reverse engineer from there? I doubt they do this, but if the dat
by dehrmann 4y ago
> Surely you can just run the card through a reader before and after taking some journeys and reverse engineer from there?
I doubt they do this, but if the data's encrypted with a good cipher used correctly, all you'll be able to detect is that it's changed.
- lxgr 4y agoThat does not prevent replay attacks, though. To thwart these, a stored-value system needs to eventually go online and synchronize a compromised card list, use (actively tamper and replay resistant) smartcards, or both.