A fork is not an attack. It is a fork. Bitcoin does not care about forks, because they are not Bitcoin.
Hm - that's a bit too simple. We had e.g. a levelDB fork - so if majority follows this fork - this is still Bitcoin.
This bugfix of the levelDB issue is a bad example as it has nothing todo with the bitcoin protocol. It fixes a bug of the Bitcoin Core client, not the bitcoin protocol.
There are other implementations of the bitcoin protocol which do not use levelDB at all (eg bitcoinj or NBitcoin).
A software fork/bugfix does not necessarily mean a bitcoin fork.
Bitcoin only forks if there are changes in the bitcoin protocol and/or consensus rules. If some implementations of the protocol don't follow the new rules you would fork bitcoin into more than one coin in the worst case.
An implementation specific bugfix unrelated to the bitcoin protocol/rules would never fork bitcoin.