function cancelOffer does not check if the offer is not already canceled, thus it is possible to invoke it again and again. It has no impact on security, just emits the event but I think it doesn't make sense to allow canceling the same offer twice.
Recommended Mitigation Steps
Solution: require that cancelledOffers[hash] is false.
Handle
paulius.eth
Vulnerability details
Impact
function cancelOffer does not check if the offer is not already canceled, thus it is possible to invoke it again and again. It has no impact on security, just emits the event but I think it doesn't make sense to allow canceling the same offer twice.
Recommended Mitigation Steps
Solution: require that cancelledOffers[hash] is false.