ck - Auction can be started without previous one being settled

[github-actions[bot]]

ck

high

Auction can be started without previous one being settled

Summary

Auction can be started without previous one being settled

Vulnerability Detail

Starting a new auction uisng the start_auction function does not check whether the previous auction has been settled:

    # epoch_start has already been set and is in the past
    if self.epoch_start != 0 and self.epoch_start <= block.timestamp: 
        raise "auction already started"

So if an auction has ended and not been settled, a new one could be started with stale values of highest_bid, highest_bidder and current_epoch_token_id.

Impact

A new auction can be started that would break intended epoch and bidding functionality.

Code Snippet

https://github.com/sherlock-audit/2023-02-fair-funding/blob/main/fair-funding/contracts/AuctionHouse.vy#L217-L242

Tool used

Manual Review

Recommendation

Add a check to determine if there is an auction that has not been settled and revert if an attempt to start an auction is done.

Duplicate of #39