What are the main security risks and smart contract vulnerabilities in Hedera (HBAR) network

Smart Contract Vulnerabilities: EVM Compatibility Risks and Code Audit Gaps in Hedera's Besu Implementation

Hedera's adoption of Hyperledger Besu for its EVM implementation introduced significant compatibility challenges despite offering developers familiar Solidity environments. While Besu enables straightforward dApp migration from Ethereum, fundamental architectural differences create distinct vulnerability surfaces. Hedera's account model and transaction processing mechanisms diverge from Ethereum mainnet, particularly regarding precompiled contracts and the gas model, which uses ops-based throttling rather than pure gas consumption. These differences can mask vulnerabilities undetectable in standard Ethereum audits.

The March 2023 exploit targeting SaucerSwap and Pangolin demonstrated these risks concretely. Attackers exploited smart contract vulnerabilities through the decompiling process, stealing approximately $600,000 in tokens. The incident revealed gaps in code audit coverage specifically tailored to Hedera's Besu implementation nuances. While tools like Mythril, Slither, and MythX remain compatible with Hedera's EVM, they may not fully detect Hedera-specific issues involving reentrancy, integer overflow, and precompile interactions.

NCC Group and other security firms have conducted audits, yet comprehensive coverage remains challenging. Developers must implement additional verification practices beyond standard Ethereum security models, including testing against Hedera's unique consensus mechanisms and account restrictions to ensure robust protection.

Network Attack Surface: Hashgraph Consensus Mechanism Security and Byzantine Fault Tolerance Limitations

The Hedera network employs a Hashgraph consensus mechanism based on asynchronous Byzantine Fault Tolerance (aBFT), representing one of the highest cryptographic standards in distributed systems theory. This consensus architecture enables HBAR to achieve agreement across a decentralized network without requiring energy-intensive voting or block production mechanisms inherent to traditional blockchain systems.

The Byzantine Fault Tolerance properties of Hedera's implementation allow the network to reach consensus even when up to 25% of nodes behave maliciously or become unavailable. This mathematical guarantee derives from the gossip-about-gossip protocol, where nodes communicate event information asynchronously—without requiring synchronized clocks or bounded message delays. The resulting system achieves eventual consistency while maintaining fast message propagation across the network.

However, despite these theoretical strengths, the Hashgraph consensus mechanism presents certain operational considerations. The aBFT model's resilience depends on accurate identification and isolation of malicious nodes, which in practice requires effective monitoring infrastructure. Additionally, the consensus mechanism maintains security only when the assumption that fewer than one-third of nodes are Byzantine-faulty holds true—a condition requiring robust node distribution and validator diversity.

Further, while the consensus mechanism demonstrates exceptional throughput capabilities exceeding 10,000 TPS, its security guarantees remain contingent on the integrity of the underlying Hedera network's validator set composition and the absence of coordinated attacks that could overwhelm the distributed ledger's consensus parameters beyond the designed fault tolerance thresholds.

Centralized Custody Risks: Exchange Custody Dependencies and Unauthorized Fund Transfer Incidents in HashPack Wallet

Relying on centralized exchange custody for HBAR introduces significant vulnerabilities that extend beyond individual account security. When users hold HBAR tokens on centralized exchanges rather than maintaining self-custody, they face exposure to custodian insolvency and operational failures. The primary concern stems from inadequate safekeeping practices, where loss of private keys or institutional collapse can result in permanent fund loss. Exchange custody dependencies create single-point-of-failure risks, particularly when using lesser-regulated platforms that lack institutional-grade security protocols.

HashPack Wallet incidents illustrate how even dedicated Hedera wallets encounter unauthorized transfer challenges. Recent cases reveal that fund losses often stem from social engineering and address verification failures rather than wallet protocol flaws. Users unknowingly interact with malicious QR codes or verify incorrect addresses before confirming transactions, resulting in HBAR being sent to attacker-controlled accounts. Once scammers obtain funds, they typically route stolen HBAR through centralized exchanges for rapid liquidation. Security practitioners recommend always double-checking recipient addresses and memos before transaction confirmation, and gathering transaction IDs through HashScan when investigating suspected theft to track fund movement patterns.

Governance Concentration: Hedera Council's Consensus Node Monopoly and Decentralization Challenges

Hedera's current architecture demonstrates significant governance concentration through its reliance on the Hedera Council, which operates all consensus nodes on the network. While comprising up to 39 term-limited organizations across six continents, this permissioned model creates structural centralization risks distinct from truly decentralized networks. Each council member holds a single vote, concentrating consensus node operation within a predetermined set of entities rather than allowing open participation. This permissioned infrastructure layer, though designed to ensure network stability and security during early phases, fundamentally contradicts blockchain decentralization principles and introduces potential attack vectors through council member compromise or collusion.

The network acknowledges these constraints through its roadmap toward full permissionlessness, where any business or individual could theoretically operate consensus nodes anonymously and earn HBAR rewards. However, this transition remains incomplete, leaving the network vulnerable to governance risks inherent in concentrated decision-making structures. The third phase activation requires reaching all 39 council positions and deploying hundreds of permissioned nodes—milestones not yet achieved. Until permissionless consensus becomes reality, Hedera's security posture remains dependent on the trustworthiness and operational integrity of a limited council, presenting counterparty risks and potential single points of failure that sophisticated adversaries might target.

FAQ

What are the most common smart contract vulnerabilities in the Hedera (HBAR) network?

Hedera smart contracts commonly face code defects and logic errors. In March 2023, attackers exploited vulnerabilities in the mainnet smart contract service, illegally transferring HTS tokens from target accounts. Key risks include insufficient code audits, authorization flaws, and reentrancy attacks affecting DEXs like SaucerSwap and HeliSwap.

Hedera的安全架构相比以太坊和Solana有什么优势和劣势？

Hedera's Hashgraph consensus offers advantages: instant finality, 10,000 TPS throughput, enterprise governance by Google and IBM, lower fees ($0.0001). Disadvantages: less developer ecosystem maturity than Ethereum, smaller validator network compared to Solana's scale.

How to identify and prevent re-entrancy attacks in Hedera smart contracts?

Use the noReentrant() modifier on external functions and implement a boolean lock mechanism. Set the lock to true before fund transfers and reset to false after completion. This prevents recursive calls from exploiting the contract during execution.

Hedera network's consensus mechanism (Hashgraph) - are there security vulnerabilities?

Hedera's Hashgraph implements Asynchronous Byzantine Fault Tolerance (ABFT), providing strong security guarantees. It uses cryptographic hashing and handles network delays effectively. No critical vulnerabilities have been identified in the core consensus mechanism itself.

Hedera上的DeFi应用面临的主要风险和审计建议是什么？

Hedera DeFi应用主要风险包括智能合约漏洞、重入攻击和中心化风险。审计建议包括进行第三方代码审计、实施多重安全防护、进行压力测试，以及建立完善的风险管理和应急响应机制。

Does Hedera's smart contract gas model and cost structure pose security risks?

Hedera's gas model presents potential security concerns as complex contracts may face resource exhaustion attacks. However, Hedera's deterministic fees and predictable costs actually reduce certain attack vectors compared to traditional networks. Security depends on proper contract auditing and best practices.

Hedera生态中已发生过哪些安全事件或合约漏洞？

Hedera在2023年3月遭遇重大智能合约漏洞攻击，黑客利用主网代码缺陷从多个DEX（如SaucerSwap、HeliSwap）非法转移HTS代币。官方迅速禁用受影响节点遏制攻击。这一事件凸显了网络安全防御的重要性。