Cardano DDoS attempt ends with attacker losing funds

Yesterday an attack was attempted on the Cardano blockchain.

The attacker used reference scripts to pack 194 small smart contracts into each transaction (Cardano transactions per transaction, amazing right). The actual scripts had no function and unsigned, and because of that the attacker could make them cheaply for about 0.9ADA per transaction, as the fee calculation charges for execution steps. The attacker then tried to flood the mempool with these large transactions.

I was using the chain at the time, making some stablecoin loans and token swaps, there didn't seem to be any problems that I noticed, my transactions proceeded normally. SundaeSwap have said they processed over 5000 trades and most of them completed within a single block.

Because the attack didn't really impact the chain significantly, it took a while for the community to notice. However as more people became aware, an X space launched and the community formulated a plan.

A few community Devs built a script that removed 2ADA from the attacker, each time they created one of the 194 scripts. All of a sudden the cost of the attack went from 0.9ADA per transaction to 388.9 ADA per transaction. The attackers wallet started to get drained quickly and the attack stopped.

Its worth noting this all happened in a completely decentralised way, no central actors had to co-ordinate the response, the chain remained performant and users were largely unimpacted. If you compare this with DDoS on some other projects, well...

The Cardano community has launched a commemorative meme token $DDOS which sold out almost immediately.

While it would be foolish to predict Cardano could never be successfully attacked, the project is built like a tank.