Cross-Chain Bridge Security Audits
Bridges are the highest-risk infrastructure in crypto. They combine multi-chain logic, off-chain relayers, consensus validation, and massive asset custody into a single attack surface. Bridge exploits account for over $3 billion in losses, more than any other protocol category.
Why Bridges Are the Hardest Audit Target
Cross-chain bridges are architecturally unique. They span multiple blockchains, rely on off-chain infrastructure, and custody assets from every chain they connect. A vulnerability in any layer (smart contracts, relayer logic, validator sets, or message verification) can drain every asset the bridge holds.
The Ronin bridge hack ($625M), Wormhole ($320M), and Nomad ($190M) all followed the same pattern: a single point of failure in the bridge's validation logic that allowed attackers to mint or withdraw assets without legitimate cross-chain messages. These aren't edge cases. They're the defining exploit category of the 2022-2025 era.
Our Methodology
Our bridge audit methodology covers the full cross-chain attack surface, not just the smart contracts.
Cross-Chain Architecture Mapping
Map the full bridge system: source chain contracts, destination chain contracts, relayer/validator infrastructure, message formats, and asset custody model.
Message Verification Audit
Review the mechanism that validates cross-chain messages. This is where most bridge exploits originate: forged or replayed messages.
Asset Custody Review
Analyze lock/mint and burn/release mechanisms. Verify that asset accounting is consistent across chains and resistant to manipulation.
Relayer & Validator Security
Evaluate the trust model for off-chain components. Assess validator threshold, key management, and liveness assumptions.
Report & Remediation
Multi-chain findings with cross-chain impact analysis. Re-audit of all fixes.
Vulnerability Classes We Target
These are the vulnerability patterns most relevant to this audit type: the ones that cause real losses.
Message Forgery
Insufficient validation of cross-chain messages allowing attackers to fabricate withdrawal or minting requests.
Replay Attacks
Valid messages replayed across chains or re-submitted to drain additional assets beyond the original transaction.
Validator Compromise
Centralized or insufficient validator sets where compromising a threshold of signers grants full bridge control.
Asset Accounting Mismatches
Inconsistencies between locked and minted assets across chains, enabling unbacked withdrawals.
Relayer Manipulation
Off-chain relay infrastructure that can be censored, delayed, or corrupted to influence bridge state.
Frequently Asked Questions
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