Unchecked output of the ECDSA recover function.md

82 - Unchecked output of the ECDSA recover function

The ECDSA.recover function (in version 2.5.1) returns address(0) if the signature provided is invalid.

This function is used twice in the Futureswap code: Once to recover an oracleAddress from an oracleSignature, and again to recover the user’s address from their signature.

If the oracle signature was invalid, the oracleAddress is set to address(0).

Similarly, if the user’s signature is invalid, then the userMessage.signer or the withDrawer is set to address(0).

This can result in unintended behavior.

Recommendation:

Consider reverting if the output of the ECDSA.recover is ever address(0)

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Slide Screenshot

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Slide Text

• OpenZeppelin Audit Futureswap V2 Finding M03
• Error Handling
• Medium Severity
• ECDSA.recover
• Unchecked address(0)
• ECDSA.recover address(0) -> Revert

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References

• Youtube Reference
• Medium Risk severity finding from OpenZeppelin’s Audit of Futureswap V2

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