The _check function in the contract assumes that Chainlink price feeds always have 8 decimals, which is incorrect. This can lead to incorrect price scaling and potential mispricing issues for assets where the Chainlink oracle uses a different decimal format.
Chainlink price decimal is assumed to be always 8 which is not always true. More so, even if it were 8 for the relevant tokens used in the protocol, there is no guarantee it will remain the same.
The contract may miscalculate price differences.
Manual Review
add the loc: uint256 chainlinkDecimals = AggregatorV2V3Interface(dataFeed[token]).decimals(); to the _check() function.
Please read the CodeHawks documentation to know which submissions are valid. If you disagree, provide a coded PoC and explain the real likelihood and the detailed impact on the mainnet without any supposition (if, it could, etc) to prove your point. Keepers are added by the admin, there is no "malicious keeper" and if there is a problem in those keepers, that's out of scope. ReadMe and known issues states: " * System relies heavily on keeper for executing trades * Single keeper point of failure if not properly distributed * Malicious keeper could potentially front-run or delay transactions * Assume that Keeper will always have enough gas to execute transactions. There is a pay execution fee function, but the assumption should be that there's more than enough gas to cover transaction failures, retries, etc * There are two spot swap functionalies: (1) using GMX swap and (2) using Paraswap. We can assume that any swap failure will be retried until success. " " * Heavy dependency on GMX protocol functioning correctly * Owner can update GMX-related addresses * Changes in GMX protocol could impact system operations * We can assume that the GMX keeper won't misbehave, delay, or go offline. " "Issues related to GMX Keepers being DOS'd or losing functionality would be considered invalid."
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