Pragma flags 6 price feeds as critical risk following $3.5M Starknet lending exploit

Oracle provider Pragma classified 6 of 22 mainnet market and rate feeds as critical risk in a Sept. 18 assessment, warning lenders that an available token price does not establish that collateral can be sold to cover a loan.The liquidity report followed a Sept. 17 borrowing exploit at Nostra, a lending protocol on Starknet. Nostra’s account reported that a manipulated NSTR oracle price allowed one account to borrow approximately $3.5 million of other assets against NSTR collateral.Pragma placed BROTHER, DAI, DOG, EKUBO, LORDS and NSTR in its critical category, with nine other feeds rated high risk. The assessment does not establish that every listed feed is used as collateral.Why an oracle price is not enoughAn oracle supplies a valuation. Liquidation requires selling collateral, and a thin market may not absorb that sale near the quoted price. A loan can be backed by an apparent value that cannot be realized when repayment depends on selling the token.At token quantities valued by the oracle at $10,000, sell-quote deterioration was about 15% for NSTR, 17% for EKUBO, 22% for LORDS, and 20% for BROTHER, measured against quotes for $10 sales.Pragma’s Sept. 18 snapshot showed indicati...