Tether's asset interoperability protocol, USDT0, has disclosed details of its security architecture following the Kelp security incident. According to Odaily, the system currently employs a proprietary Decentralized Verification Network (DVN) with message veto power. It requires consensus from three independent validators using different codebases to achieve a 3/3 agreement before cross-chain messages can be settled. The current verification nodes include USDT0's proprietary DVN, LayerZero, and Canary, with plans to expand to 4/4 and 5/5 verification mechanisms.
USDT0 also stated that all multi-signature transactions undergo multiple reviews by internal teams, external security teams, and auditing firms before signing. The relevant contracts have been audited by Guardian and OpenZeppelin and are part of a $6 million bug bounty program on Immunefi.