事件の概要 発生原因
2020/2/18 63.3
(2,378ETH) bZx
KyberSwap
Synthetix
Flash Loan
Oracle
bZxOracleETHsUSD
2,378ETH
1. Flash Loan(a)-(e)1
a) bZx7,500ETHFlash Loan
b) KyberSwap540ETH92,419sUSD360ETH
63,584sUSD(900ETH156,003sUSD
KyberSwapUniswapETH
sUSDKyberSwapsUSD3
KyberSwap0.00372ETH/sUSD
30.00899ETH/sUSD
c) Synthetix 6,000ETHsUSDsUSD
3,518ETH943,837sUSD2,482ETH
0.00372ETH/sUSD
d) bZx110sUSD6,796ETHsUSD
4,000ETHbZxKyberSwap
OraclesUSD6,796ETH
e) bZx7,500ETH2,378ETH
2,378ETH6,796ETH3,082ETH
7,500ETH
bZxOracle
KyberSwap
kyberSwapsUSD
bZx KyberSwapDEX
SynthetixDEX Flash LoanEthereum1(15)KYC
Oracle
ETHEthereum sUSDSynthetix
2,378ETH6,796+(7500-900-3518) -7500=2,378
2-5-3 Flash Loan Attack #2
Flash Loan Attack #2
bZx
1(a). 7,500ETH
1(e). 7,500ETH
2,378ETH
Synthetix
Oracle
KyberSwap
bZx
UniSwap
1(b). 900ETH156,003sUSD
sUSD
1(c). 3,518ETH
943,837sUSD
1(d). 110sUSD6,796ETH