From https://github.com/WICG/trust-token-api https://github.com/WICG/trust-token-api > Token Exhaustion Attack > Issuers issue many tokens at once, so users h

From https://github.com/WICG/trust-token-api https://github.com/WICG/trust-token-api > Token Exhaustion Attack > Issuers issue many tokens at once, so users have a large supply of tokens. > When the issuer detects a site is attacking its trust token supply, it can fail redemption (before the token is revealed) based on the referring origin, and prevent browsers from spending tokens there. I think there’s an interesting trade-off between attack surface and specificity of the token here. A token meaning “This user has only accessed 6 sites in this network” is meaningful only if there’s a single token, as the next access can cause the token to be inconsistent with reality (It states a falsity now). At the same time, it states the issuer can block redemption based on the referrer. I think that’ll be interesting, as an allow list format will lead to only “big players” being able to use this API (As they are the only ones who they trust to not adversarially redeem tokens) whereas a deny list you’re playing a game of whack-a-mole where new domains can be popped up for this purpose. edit: added the last part of the quote for completeness