📌 Flash Loan Attack Summary

A flash loan attack is a type of exploit in decentralised finance (DeFi) where a person borrows a large amount of cryptocurrency for a very short time, usually within a single blockchain transaction. The attacker uses this borrowed money to manipulate prices or exploit vulnerabilities in smart contracts, and then returns the loan before the transaction ends. Because the loan is repaid instantly, the attacker does not need to provide collateral, making these attacks fast and difficult to stop.

🙋🏻‍♂️ Explain Flash Loan Attack Simply

Imagine you could borrow a huge amount of money for just a few seconds, use it to trick a system into giving you extra rewards, and then return the money before anyone noticed. That is what happens with a flash loan attack, only everything happens automatically with computer code.

📅 How Can it be used?

A DeFi project must audit smart contracts to prevent flash loan attacks that could drain its assets or manipulate token prices.

🗺️ Real World Examples

In 2020, the bZx protocol was attacked using a flash loan. The attacker borrowed a large sum of Ether, used it to manipulate the price of an asset on one exchange, and took advantage of the price difference on another platform to make a profit, all within one transaction.

The PancakeBunny protocol suffered a flash loan attack where the attacker borrowed funds, manipulated the price of its token, and then sold the tokens at artificially high prices, causing users to lose millions.

✅ FAQ

A flash loan attack happens when someone borrows a huge amount of cryptocurrency for just a few seconds, uses it to take advantage of weaknesses in a system, and then pays it back almost instantly. Since the loan is so short and does not need any collateral, it is a quick way for attackers to try to manipulate prices or trick smart contracts without risking their own money.

Flash loan attacks are tough to stop because the loans happen and are repaid within one transaction, leaving little time to react. Attackers do not need to provide any security for the loan, so they can act quickly and leave no trace. This makes it hard for developers and exchanges to spot and block suspicious activity before any damage is done.

To guard against flash loan attacks, developers can make their smart contracts more secure by checking for unusual activity or adding extra steps to verify transactions. Regular security checks and updates also help. It is important for DeFi projects to learn from past attacks and build stronger defences to keep users and funds safe.

📚 Categories

• Anti Attack
• Blockchain
• Threat Detection and Response

🔗 External Reference Links

Flash Loan Attack link

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