A similar attack happened almost exactly one year ago. Unfortunately due to the apparent lack of support from the MOAC blockchain developers, while we are able to identify the problem, we could not mitigate it without a proper node software update. The blockchain has been split. Check the block height on the screenshot below.
This causes the whole blockchain to be unstable and moreover poses a threat to other pools we run. Our automated monitoring system prevents the bad outcomes of the denial of service attack, but nonetheless it causes extensive CPU and RAM usage on our dedicated server infrastructure. For this reason, we were forced to turn off both MOAC Solo and PPLNS pools on February 3rd.
For the time being the MOAC pools are stopped until the attack is over. We are considering delisting the MOAC cryptocurrency because this is not the first time the attack runs and there is only so little we can do from our side.