Incident Overview
Carol Protocol suffers flash loan exploit, resulting in a loss of $61,164 USD (29.92 ETH).
On November 30th, 2023, Carol Protocol, a project running on the Base chain, experienced a flash loan exploit due to a smart contract vulnerability. The root cause of this exploit was identified as manipulation of the stake amount. The contract's design flaw lies in its reliance on Uniswap Pair Balance to determine user balances, a metric that is susceptible to manipulation.
The stolen funds were distributed between multiple addresses and then transferred to another scammer's EOA. The total loss amounted to $61,164 USD, equivalent to 29.92 ETH.
Binance Smart Chain:
Attacker address:
https://basescan.org/address/0x5AA27D55…bC3144
Funds Holder as of Dec 14, 2023:
https://basescan.org/address/0xcDd37Ada…4A2af2
Malicious transactions:
https://basescan.org/tx/0xd962d397…b4185c
Malicious contract:
https://basescan.org/address/0xc4566ae9…780b2c
Incident Report
Protocol Information
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.
What Auditors Should Check
If you're auditing a protocol with similar architecture to Carol Protocol, these are the critical security checks that could have prevented this incident (November 2023).
- Verify all logic paths related to Flash Loan Attack 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
Master these auditing techniques with hands-on labs and real exploit scenarios in the Smart Contract Hacking course.
Free TrialSecurity Audit History
- Audit Report 1 Report
Related Attack Classes
The technique used in this hack maps to these vulnerability classes in our security curriculum:
Sources & References
- 01
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02
Web Archive https://archive.ph/Jly4j
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