Packet filters and firewalls are an important component of any defense-in-depth security strategy. Which two types of threats can IP Filter be deployed as an effective countermeasure against? (Choose two.)

A.
a Christmas Tree scan

B.
an attempt to log in to a system using SSH by an unauthorized user

C.
an attempt to exploit a SQL injection vulnerability in a web storefront application

D.
an attempt to exploit a buffer overflow vulnerability in rpcbind, originating from a host on an authorized network

E.
an attempt to exploit a buffer overflow vulnerability in rpcbind, originating from a host on an unauthorized network