The following would probably be illegal so do not actually do this. But
what if... there are just 4 billion IPv4 addresses. Scanning that
address-space for open NTP is trivially done in a few hours. Abusing these
servers for reflection attack is as trivial, hence the problem. How can we
get the responsible parties to fix their NTP servers?
Answer: DDoS them. With their own service.
Or it could be a DDoS defense. As a victim of an ongoing NTP reflection
attack, you know exactly the IP-addresses of the vulnerable NTP servers
used to attack you. Make them stop by sending back forged NTP packets, so
they use up their available bandwidth to DDoS each other instead of you.
This could even be automated. If you let them attack their next-hop as
discovered by traceroute, it might not even be illegal or harmful. They
will only bring down their own link, do no more harm to the internet at
large and they can fix it by stopping the NTP service. If they are part of
an ongoing DDoS attack it is just self defence to shut them down in the
least harmful way possible.
It's never appropriate to respond to abuse with abuse. Not only is
it questionable/unprofessional behavior, but -- as we've seen -- there
is a high risk that it'll exacerbate the problem, often by targeting
innocent third parties.
I understand the frustration but this is not the way.
The following would probably be illegal so do not actually do this. But
what if... there are just 4 billion IPv4 addresses. Scanning that
address-space for open NTP is trivially done in a few hours. Abusing these
servers for reflection attack is as trivial, hence the problem. How can we
get the responsible parties to fix their NTP servers?
Answer: DDoS them. With their own service.
One of the attacks that was mitigated the fastest was the SQL Slammer worm due to the broad impact it had across the internet.
The OpenNTP and OpenResolver projects provide inventories of these servers for operators to take action and to take to their customer cone.
Or it could be a DDoS defense. As a victim of an ongoing NTP reflection
attack, you know exactly the IP-addresses of the vulnerable NTP servers
used to attack you. Make them stop by sending back forged NTP packets, so
they use up their available bandwidth to DDoS each other instead of you.
This could even be automated. If you let them attack their next-hop as
discovered by traceroute, it might not even be illegal or harmful. They
will only bring down their own link, do no more harm to the internet at
large and they can fix it by stopping the NTP service. If they are part of
an ongoing DDoS attack it is just self defence to shut them down in the
least harmful way possible.
Do you have a letter from the local law enforcement or legal counsel on this topic? If so, can you please share it with the class or submit a presentation to an upcoming conference on this?
They both follow to the appropriate RFC's, contrary to all those AS
+ /24 that keep allowing spoofing source IP address.
The victims of attacks could get the Tiers to follow back the source
of the attack instead, but the corporations involved have more money
than the small guy you'll bash for having the balls of running a
resolver for his roaming customers.