Client Profile
The client is a decentralized finance (DeFi) platform enabling cross-chain asset swaps, yield farming, and liquidity provision across Ethereum, Arbitrum, and Polygon. With over $300M in total value locked (TVL) and frequent protocol upgrades, the client needed assurance against evolving threats – including contract-level exploits, bridge vulnerabilities, and oracle manipulation. Their goal was to proactively uncover and fix exploitable security gaps before malicious actors could exploit them.
Challenges Faced
Key security concerns included:
- Complex cross-chain architecture increasing attack surface
- Potential for flash loan and price oracle manipulation
- Smart contract upgradeability introducing logic flaws
- Lack of prior formal penetration testing against the protocol stack
Solution
COE Security conducted a comprehensive Blockchain Penetration Testing Engagement, combining:
- Smart Contract Exploit Simulation: Assessed reentrancy, logic flaws, and access control gaps in Solidity-based contracts
- Cross-Chain Bridge Testing: Validated integrity, transaction verification, and replay protections on bridge infrastructure
- Oracle Manipulation Testing: Simulated time-weighted average price (TWAP) attacks and single-source price feeds
- Infrastructure and API Layer Testing: Probed RPC endpoints, GraphQL APIs, and validator node exposure
Offensive Testing, Defensive Results
- Exploited flash loan loophole that could drain liquidity pools within 4 seconds
- Bypassed contract access restrictions via misconfigured proxy upgrade path
- Identified insecure fallback functions exposing core logic to misuse
- Flagged insecure randomness source in reward distribution logic
- Found unprotected emergency functions callable by non-admin accounts
Strategic Insights & Governance Alignment
- Delivered risk-scored attack surface map across smart contracts, bridges, and APIs
- Developed mitigation strategies for high-risk functions with compensating controls
- Advised on secure deployment practices and smart contract lifecycle governance
- Created a custom checklist for secure upgrades and testnet-to-mainnet migrations
Offensive Security for Blockchain
- Full-stack Blockchain Penetration Testing
- Smart Contract Exploit Simulation
- Flash Loan & Oracle Abuse Testing
- Bridge & Cross-Chain Protocol Attacks
- API & RPC Endpoint Security Assessment
- Secure Upgrade & Proxy Testing
- Wallet, Signature & Transaction Tampering
- Blockchain Fuzzing & Static Analysis
- DeFi Protocol Adversarial Simulation
- Post-Test Code Review & Patch Validation
Implementation Details
- Audited and tested over 30 smart contracts and 3 bridge protocols
- Conducted black-box and white-box testing in staging and production environments
- Used proprietary fuzzers and exploit kits tailored for DeFi
- Delivered a final PenTest report with detailed Proof of Concept (PoC) exploits
- Conducted a joint patch review session with the client’s developers and DevOps team
Results Achieved
- Identified 21 vulnerabilities (6 critical, 8 high, 7 medium) with zero false positives
- Enabled secure deployment of Version 2 contracts and bridge modules
- Achieved a 90% reduction in attack surface based on remediation coverage
- Helped secure a successful $50M funding round with external audit verification
Client Testimonial
“COE Security didn’t just find bugs – they understood our architecture, challenged our assumptions, and made our protocol truly resilient. Their blockchain penetration testing is top-tier.”