Sunday, June 14, 2026

Aztec

Funds lost

$2.0M

Attack type

Other

Network

Ethereum

Category

Other

Summary

In 14th June 2026, the privacy-focused Layer 2 protocol Aztec Network suffered a smart contract exploit on Ethereum mainnet targeting its legacy RollupProcessorV3 contract, resulting in a loss of approximately $2.19 million.

Details of the Exploit

The exploit targeted a logical mismatch inside the processRollup() function between the transaction batch verified by the zero-knowledge (ZK) rollup proof and the transaction loop executed by the Layer-1 (L1) settlement engine. The attacker exploited this by manipulating the processed transaction parameter (numRealTxs) to 1, placing a dummy transaction in the first position, and an actual deposit transaction in the second slot. Because the ZK proof validated the entire data payload, the rollup internally credited the private funds to the attacker's state tree.

However, because numRealTxs restricted the L1 loop to parse only the first slot, the contract skipped the corresponding L1 balance deduction logic (decreasePendingDepositBalance()). This allowed the attacker to generate completely unbacked private notes out of thin air, which they subsequently withdrew into real assets across seven different tokens.

Source: De.Fi REKT Database. Data as of November 3, 2026.