Aztec Hack

TOTAL LOST $2.0M
Medium Other

Summarize with AI

ChatGPT Perplexity Claude Grok
Affected Chain 2026 Incident surface
Recovered - No recovery reported
All-Time Rank #627 By amount stolen
Protocol Type Exploit/Other Target category

Incident Overview

Quick 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.

Block Data Reference

Attacker Address: 0x0f18d8b4…7edd17

Attack Transaction: 0x074ec931…9aeeb1

Incident Report

Protocol / Project Aztec
Date of Incident
Attack Technique Other
Classification Other
Primary Source View Post-Mortem #1 View Post-Mortem #2 View Post-Mortem #3

Protocol Information

Protocol Type Exploit/Other
Official Website aztec.network/
Protocol Twitter/X @aztecnetwork
Team Anonymous
Source Code Unverified

What the Attacker Needed to Succeed

Understanding the prerequisites for this type of attack helps auditors identify protocols that are most at risk and helps developers build better defenses.

Technical Knowledge Deep understanding of other and Solidity and EVM internals
Capital Required Seed capital to cover gas and initial position setup
On-Chain Access Ability to interact with smart contracts and deploy a custom exploit contract
Protocol Analysis Identification of the exploitable vulnerability in Aztec's contract logic - root cause: other
Execution Speed Precise transaction ordering and timing to exploit the vulnerability within a single atomic block
Obfuscation Plan A strategy to launder and move stolen funds - typically through mixers, cross-chain bridges, or decentralized DEX swaps to resist tracing

What Auditors Should Check

Could this have been caught in audit? Likely — with a thorough Other audit checklist and test coverage

If you're auditing a protocol with similar architecture to Aztec, these are the critical security checks that could have prevented this incident (June 2026).

  • Verify all logic paths related to Other are guarded by proper access controls and input validation
  • Review privileged functions (owner, admin, governance) for potential abuse vectors - centralization risks should be documented and bounded with timelocks or multi-sigs

Master these auditing techniques with hands-on labs and real exploit scenarios in the Smart Contract Hacking course.

Free Trial

Sources & References

Browse all hacks

These hacks used the same attack technique. Understanding the pattern helps prevent future exploits.

Raydium $1.3M
Other
ATM Token $244K
Other
Alephium $815K
Other
MoneyMon $85K
Other
RetoSwap $2.7M
Other
HermesVault $30K
Other

Learn to Prevent the Next Aztec

The Aztec hack is one of many attacks that skilled auditors are trained to detect before deployment. Master real exploit patterns and defense techniques with hands-on Web3 security training.

Start Free Trial Browse Attack Library
Recreate exploit patterns safely Free Trial