Since 1510 pacific time over 100 pages of XMAS port attacks. Each page has 10 entries. These should be blocked before they hit up link feed.
Viasat has "real" internet where very few ports are blocked and "incoming" is permitted.
YOU need to check your router and verify it's firewall is "on" and you have no ports forwarded.
If you are not using a router, then your Operating System firewall needs to be checked.
You should be able to make Operating System firewall entries (or rules) to block the attack. This is very important if the attacks are coming in port 80 (broadcast port).
You also should be using anti-virus that will also stop the attack.
If the bad-guy attacks don't see a place to go and be received, they won't be sent if they are always rejected. Blocked by firewall stops them from using up your data because the "ack" won't be sent back to them to make the trip successful (and your system won't be asking for more).
I have not had anyone use up my data with an outside attack to my modem no. But I can see how it could be done and cause the use of data. If someone is targeted you that hard, call support and ask for a new dhcp lease. find out how your being targeted. dont click dumb links.