Yesterday, a re-spending-like transaction was on the Filecoin network, which resulted in several million dollars being credited to the exchange wallet twice, states CoinDesk .
In the blockchain, the transaction was not executed twice but on Binance exchange, where the funds were sent, twice credited them to the miner's account. This was due to a "serious bug" in the remote procedure call (RPC) code.
Re-spending occurs when the same funds are spent twice at the blockchain level. Bitcoin's Proof-of-Work algorithm was created to prevent such situations. But, the Filecoin bug allows users to re-spent the same deposits to exchanges. The miners who discovered the problem claim that they have already managed to identify other similar cases.
All exchanges working with Filecoin use the same procedures for conducting deposits, so in theory, the bug can be reproduced on any of them. Binance, Huobi, and other platforms have already stopped FIL deposits, and Filecoin developers have opened trial on GitHub.