Canto - Team_FliBit's results

Lines of code

https://github.com/code-423n4/2023-06-canto/blob/a4ff2fd2e67e77e36528fad99f9d88149a5e8532/Canto/x/coinswap/types/params.go#L34

Vulnerability details

Impact

In the documentation, it is stated that:

For risk management purposes, a swap will fail if the input coin amount exceeds a pre-defined limit (10 USDC, 10 USDT, 0.01 ETH) or if the swap amount limit is not defined.

However, in the code it defined as:

sdk.NewCoin(EthIBCDenom, sdk.NewIntWithDecimal(1, 17))

This is incorrect since ETH has 18 decimals so the NewCoin with 17 decimals will be 0.1 ETH and not 0.01 ETH.

Since the maximum actual ETH input is 10x the stated limit and, at current prices, 18x the USDC/USDT limit, it is clear that the risk management intended by the protocol through input limits, is ineffective.

Proof of Concept

https://github.com/code-423n4/2023-06-canto/blob/a4ff2fd2e67e77e36528fad99f9d88149a5e8532/Canto/x/coinswap/types/params.go#L34

https://github.com/code-423n4/2023-06-canto/blob/a4ff2fd2e67e77e36528fad99f9d88149a5e8532/README.md

Tools Used

Manuel Review

Recommended Mitigation Steps

Change the NewCoin Denom to 16 decimals.

sdk.NewCoin(EthIBCDenom, sdk.NewIntWithDecimal(1, 16))

Assessed type

Decimal