CVE-2026-67581High· 7.5▾ TwilightAuthentication Bypass by Capture-replay in ZenHive mpp allows an unauthenticated remote client to obtain paid resources by resubmitting one settled on-chain transfer. MPP.Methods.EVM.verify/2 accepts a transaction-hash credential and ma…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 41.3 · likelihood 0.1 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Exploit-prediction probability, daily snapshots since Sep 10.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.5%
Authentication Bypass by Capture-replay in ZenHive mpp allows an unauthenticated remote client to obtain paid resources by resubmitting one settled on-chain transfer.
MPP.Methods.EVM.verify/2 accepts a transaction-hash credential and matches a transfer purely on token, to and amount (ERC-20) or to and value (native). It binds the proof neither to the challenge being verified nor to any record of prior use, and the generic MPP.Plug dedup store keys on challenge.id, which is regenerated for every 402 response. On a static-price route, a single historical transfer matching the charge therefore satisfies an unbounded number of later charges, including transfers an attacker can read off a public block explorer.
This issue affects mpp: from 0.3.0 before 0.6.3.
machine_payments_protocol >= 0.3.0, < 0.6.4Upgrade past the affected range:
machine_payments_protocol 0.6.4Connected by shared product, vendor, weakness, or advisory.
CVE-2026-73136High· 7.5Authentication Bypass by Capture-replay in ZenHive mpp allows an unauthenticated third party to obtain paid resources by replaying a transfer settled by an unrelated payer. MPP.Methods.Tempo normally binds a settled TIP-20 TransferWithM…
CVE-2026-87119High· 8.2Authentication Bypass by Capture-replay in ZenHive mpp allows an attacker holding a captured subscription activation credential to charge the payer repeatedly. The payer signs a Tempo KeyAuthorization over the chain id, key type, key id…
CVE-2026-73541High· 8.2Allocation of Resources Without Limits or Throttling in ZenHive mpp allows an unauthenticated remote client to drain the fee-payer wallet through concurrent sponsored payments, denying service to legitimate payers once it is empty. MPP.…
CVE-2026-73829Low· 3.7Time-of-check Time-of-use (TOCTOU) Race Condition in ZenHive mpp allows an unauthenticated remote client to redeem one confirmed on-chain payment for multiple paid-resource accesses. The type="hash" credential path in MPP.Methods.Tempo.…
CVE-2026-89420High· 7.1Improper Validation of Specified Quantity in Input in ZenHive mpp allows a client holding an open payment channel to obtain paid resources without being charged. MPP.Session.Actions.accept_voucher/3 in lib/mpp/session/actions.ex treats …
CVE-2026-88255Medium· 6.3Improper Validation of Unsafe Equivalence in Input in ZenHive mpp allows an unauthenticated remote client to pass the Tempo duplicate-submission gate twice with one signed transaction. MPP.Methods.Tempo reserves the pre-broadcast dedup …