#appsec

Chrome made SameSite=Lax the default and most CSRF vulnerabilities quietly stopped working. That is real protection nobody implemented, and it leaves three specific gaps, one of which turns on the fact that SameSite was never about origins in the first place.

The Capital One breach was 100 million records from one server-side request. The reason the obvious fix fails is subtler than a bad blocklist: you check a hostname, then you resolve it again to make the request, and DNS is free to answer differently the second time.