Old tokenData is used instead of new

[c4-submissions]

Lines of code

https://github.com/code-423n4/2023-10-nextgen/blob/main/smart-contracts/NextGenCore.sol#L218

Vulnerability details

Impact

When the burnToMint() function is called, a token from one collection is burned and a new token from a new collection is minted. The oldest tokenData is transferred to the newly minted token, which is incorrect.

_mintProcessing(mintIndex, ownerOf(_tokenId), tokenData[_tokenId], _mintCollectionID, _saltfun_o);

The term tokenData refers to additional data that will be stored on-chain for each minted token. The data for every token is expected to be different and once set, tokenData can not be changed in the future.

This design may introduce potential issues if a user wishes to store different data on-chain and no longer use the old tokenData.

Recommended Mitigation Steps

Add the possibility for the user to change tokenData when using burnToMint().

Assessed type

Context

[c4-pre-sort]

141345 marked the issue as sufficient quality report

[c4-sponsor]

a2rocket (sponsor) disputed

[a2rocket]

this is the intended design, burnToMint's new token inherints the burnt token tokenData.

[alex-ppg]

The Warden specifies that it is undesirable to inherit the tokenData of the burnt token for a newly minted token via burnToMint, however, the Sponsor dictates that this is expected behavior.

Given that this data is meant for off-chain purposes and the Sponsor cites this as desirable behaviour, I consider this exhibit invalid. To note, this is also detailed in the project's documentation provided during the contest.

[c4-judge]

alex-ppg marked the issue as unsatisfactory: Invalid