Bridge Failure Scenario

Overview

Bridge failure scenarios include invalid message approval, compromised guardians, contract exploits, destination execution errors, liquidity exhaustion, source reorganizations, relayer outages, paused systems, accounting mismatches, and upgrades that leave components incompatible. Failures can produce different outcomes: a delayed message, locked funds, duplicated representations, unbacked tokens, partial application execution, or irreversible loss. A successful source transaction may coexist with a failed destination call, making one status insufficient for reconciliation.

Bridge operators and integrators should document detection signals, pause authority, retry rules, refund paths, and communication responsibilities for each scenario. Payment systems need idempotent message handling and exposure limits. Incident exercises should test how balances are reconciled when chains, relayers, contracts, and indexers disagree. The workflow should be modeled as a multi-stage operation: source authorization, source inclusion and finality, message or proof production, relay, destination verification, destination execution, and destination finality. Completion of an early stage does not prove that value or instructions reached the destination.

Relevant assumptions include the validator or signer set, multisignature policy, light-client or proof design, relayers, upgrade authority, rate limits, and liquidity providers. Being described as official does not eliminate the underlying trust and control assumptions. The security model depends on the exact verification route.

Routing and custody records must bind the source asset, destination representation, contract addresses, decimals, mint or custody model, and redemption path. Two assets can share a symbol while having different issuers, contracts, or backing; symbol matching alone is therefore unsafe for crediting. Risk-control point: Bridge failures can affect either safety or liveness, requiring scenario-specific detection, reconciliation, pause, and recovery procedures.