Sonne Finance Hack

TOTAL LOST $20.0M
High Flashloan Donate Function Logic Exploit optimism

Summarize with AI

Affected Chain optimism Incident surface
Recovered - No recovery reported
All-Time Rank #229 By amount stolen
Protocol Type Lending Target category

Incident Overview

Sonne Finance is a decentralized lending protocol for individuals, institutions and protocols to access financial services. It is a permissionless, open source and Optimistic protocol serving users on Optimism. Users can deposit their assets, use them as collateral and borrow against them

Incident Report

Protocol / Project Sonne Finance
Date of Incident
Affected Chain(s) optimism
Attack Technique Flashloan Donate Function Logic Exploit
Classification Ecosystem
Primary Source View Post-Mortem

Protocol Information

Protocol Type Lending
Smart Contract Language Solidity
Official Website sonne.finance
Protocol Twitter/X @SonneFinance

Market Context at Time of Hack

Token Categories
Optimism Ecosystem

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 flashloan donate function logic exploit and Solidity and EVM internals
Capital Required Seed capital to cover gas and initial position setup
On-Chain Access Ability to interact with optimism smart contracts and deploy a custom exploit contract
Protocol Analysis Identification of the exploitable vulnerability in Sonne Finance's contract logic - root cause: ecosystem
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 β€” with a thorough Flashloan Donate Function Logic Exploit audit checklist and test coverage

If you're auditing a protocol with similar architecture to Sonne Finance, these are the critical security checks that could have prevented this incident (May 2024).

  • Verify all logic paths related to Flashloan Donate Function Logic Exploit are guarded by proper access controls and input validation - see the Flash Loans Attacks attack class for patterns
  • Review privileged functions (owner, admin, governance) for potential abuse vectors - centralization risks should be documented and bounded with timelocks or multi-sigs

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Related Attack Classes

The technique used in this hack maps to these vulnerability classes in our security curriculum:

See all Flash Loans Attacks examples β†’

Proof-of-Concept Exploits

1 PoC available
poc-exploits - sonne finance

Sources & References

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