2018-11-02, 12:25
You're talking about the sunrpc portmapper, correct ?
It's required for using sunrpc based services like NFS. If you don't need NFS, you can disable the service entirely.
OTOH, I doubt that portmapper is vulnerable to any DDOS. It's been a while since I last laid my hands on the portmap
code (I don't see any need for any notable changes since decades), but back then portmap did nothing more than
maintain a small map of rpc services and their port numbers on the same host. Updates are only allowed from localhost
(unless configured really badly), remote clients only can only query. The memory and CPU consumption is pretty limited,
so it takes a lot bandwidth to DDOS it, and that would only affect portmap itself and so nfs mount oprations.
It's required for using sunrpc based services like NFS. If you don't need NFS, you can disable the service entirely.
OTOH, I doubt that portmapper is vulnerable to any DDOS. It's been a while since I last laid my hands on the portmap
code (I don't see any need for any notable changes since decades), but back then portmap did nothing more than
maintain a small map of rpc services and their port numbers on the same host. Updates are only allowed from localhost
(unless configured really badly), remote clients only can only query. The memory and CPU consumption is pretty limited,
so it takes a lot bandwidth to DDOS it, and that would only affect portmap itself and so nfs mount oprations.
