Reentrancy Risk

Definition ∞ Reentrancy risk refers to a specific type of security vulnerability in smart contracts where an external malicious contract can repeatedly call back into the vulnerable contract before the initial execution is complete. This recursive calling allows the attacker to drain funds or manipulate state variables in an unintended manner. The flaw typically arises when a contract sends funds to an external address without updating its internal state first. It represents a severe threat to decentralized application security.
Context ∞ Reentrancy risk remains a critical security concern in smart contract development, often cited in post-mortem analyses of major DeFi exploits. A key discussion involves implementing best practices like checks-effects-interactions patterns and using reentrancy guards to prevent such attacks. Future security audits and developer education will continue to emphasize the importance of mitigating this pervasive vulnerability in blockchain code.

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→Liquid Staking

→Liquid Staking Token

→Contract

Legacy DeFi Pool Drained Exploiting Infinite Token Minting Flaw

A critical flaw in a custom stable-swap contract allowed an attacker to mint near-infinite yETH, bypassing core pool solvency checks.

A sophisticated metallic blockchain infrastructure component features a translucent blue crystalline structure, resembling frozen liquidity, encasing a central mechanism. This intricate PoS validator module integrates advanced protocol engineering, signifying asset freezing for staking. The design suggests robust cryptographic security and efficient transaction processing, crucial for decentralized finance. A subtle Ethereum symbol is visible on an adjacent circular element, underscoring its role within a distributed ledger technology ecosystem.

→Reentrancy Risk

→Contract Security

→Governance Risk

Hedgey Token Lockup Contract Logic Flaw Drains Forty-Four Million Assets

A critical logic flaw in the vesting contract's token release mechanism permitted unauthorized, repeated withdrawal of locked assets, exposing all deployed lockups.

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→Asset Loss

→Reentrancy Risk

→Asset Management

Yearn Finance Legacy Pool Drained Exploiting Infinite Token Minting Logic Flaw

A critical logic flaw in a custom stableswap contract allowed an attacker to mint unbacked yETH, leading to an immediate $9 million liquidity drain.

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→Treasury Reimbursement

→Flash Loan Attack

→Vault Security

Legacy DeFi Protocol Drained Exploiting Infinite Token Minting Logic

The legacy yETH contract's flawed minting function allowed an attacker to create 235 trillion fake tokens to drain $9M in linked liquidity pools.

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→Tokenized Staking

→Wrapped Assets

→Smart Contract Failure

Lending Protocol Exploited via Oracle Mispricing on Base Network

An external oracle failure mispriced wrstETH collateral, allowing the attacker to borrow millions against negligible deposit value, compromising protocol solvency.

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→Layer-2 Security

→Composable Stable Pool

→Asset Security

Balancer V2 Pools Drained Exploiting Smart Contract Access Control Flaw

A critical flaw in the V2 vault's access control logic permitted unauthorized `batchSwap` calls, leading to a systemic, multi-chain liquidity drain.

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→Asset Custody

→Vault Vulnerability

→Smart Contract Exploit

Balancer V2 Pools Drained Exploiting Faulty Smart Contract Access Control Logic

A logic flaw in V2's `manageUserBalance` function enabled unauthorized internal withdrawals, exposing over $128M to systemic vault drain.

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→Flash Loan Vector

→Access Control Flaw

→Audit Failure

Balancer V2 Pools Drained via Faulty Internal Withdrawal Logic

A precision error in Balancer V2's `manageUserBalance` function enabled unauthorized internal withdrawals, compromising $128M in cross-chain liquidity.