Ethereum uses node IDs to identify nodes uniquely and to route traffic between nodes based on the node discovery protocol (https://github.com/ethereum/devp2p/blob/master/discv4.md) built on Kademlia-like DHTs.
What's stopping an adversary
Mfrom spoofing as a legitimate miner by deriving their own node ID from their own public key and taking part in the node discovery protocol, which would add
M's route also to the Kadmelia-like DHTs eventually?
Since the node ID is derived from the public key of a node, can't an adversary steal key pairs from a legitimate miner and spoof as one? Couldn't this lead to a DoS attack?
If these are in fact security issues, isn't there a mechanism to blacklist spoofing miners or cut their stake (In the case of Proof-of-Stake) when Eth2.0 is released?