According to Odaily Planet Daily, Casper announced that it has fixed the testnet attack vector. On August 7, it was found that the transaction volume on the testnet increased, and the investigation found that a large number of transactions called the add_bid routine on the auction contract.

The attack exploits the fact that the add_bid function in the auction contract does not specify a minimum value, and submits tens of thousands of transactions calling the add_bid function at almost zero cost, with bid amounts close to zero.

Casper will increase the cost of add_bid to 3,500 CSPR and introduce a 10,000 CSPR minimum bid. No further action is required by the community, the mainnet is not affected, and no funds have been stolen.