E.FU

Session voucher adding no new funds is accepted without a charge in mpp, serving paid resources for free

mpp Tempo subscription key authorization is not bound to the issuing challenge, allowing a captured activation credential to be replayed

mpp writes Payment-Receipt and Cache-Control before the wrapped application runs, letting a consumer's own Cache-Control expose paid responses to shared caches

mpp Tempo keys its pre-broadcast dedup reserve on the caller-supplied transaction encoding, so a re-encoded signed transaction reserves a second slot

Non-atomic hash-credential dedup in mpp Tempo allows replay of a confirmed payment under a concurrent race

Tempo fee sponsorship in mpp bounds each transaction but not aggregate exposure, allowing concurrent sponsor-wallet drain

Static memo configuration in mpp Tempo disables per-challenge attribution binding, enabling third-party replay

On-chain transfer proof is not single-use in mpp EVM payment method, enabling cross-challenge replay

Unbounded key authorization in mpp Tempo fee-payer sponsorship inflates gas cost and sponsors access-key provisioning

Unbounded EIP-7702 authorization list in mpp Tempo fee-payer sponsorship inflates gas cost and sponsors account delegation