←back to thread

How Cloudflare blocked a monumental 7.3 Tbps DDoS attack

(blog.cloudflare.com)
265 points methuselah_in | 1 comments | 20 Jun 25 18:34 UTC | HN request time: 0s | source
Show context
londons_explore ◴[24 Jun 25 13:40 UTC] No.44366154[source]▶
A DDoS gets some fraction of the entire internet to attack a single host.

As the internet gets more users and more devices connected, the ratio of DDoS volume to a single connections volume will only get larger.

Is there any kind of solution?

replies(8): >>44366248 #>>44366352 #>>44366379 #>>44366623 #>>44366811 #>>44366991 #>>44367206 #>>44369906 #
alyandon ◴[24 Jun 25 13:49 UTC] No.44366248[source]▶
Not a 100% solution but would help greatly if ISPs:

1) performed egress filtering to prevent spoofing arbitrary source addresses

2) temporarily shut off customers that are sending a large volume of malicious traffic

replies(2): >>44366275 #>>44366336 #
alberth ◴[24 Jun 25 13:58 UTC] No.44366336[source]▶
> sending a large volume of malicious traffic

How would an ISP determine egress is malicious? Genuinely curious.

replies(5): >>44366353 #>>44366415 #>>44366743 #>>44366790 #>>44366797 #
alyandon ◴[24 Jun 25 14:06 UTC] No.44366415[source]▶
If someone is reporting malicious traffic coming from the ISP's network then an ISP should be obligated to investigate and shut off the offending customer if necessary until they've resolved the problem.
replies(1): >>44366561 #
cyral ◴[24 Jun 25 14:19 UTC] No.44366561[source]▶
How would this ever work at scale? These attacks come from thousands of compromised devices usually. e.g. Someone's smart fridge with 5 year old firmware gets exploited
replies(6): >>44366665 #>>44366824 #>>44367225 #>>44367724 #>>44372179 #>>44384126 #
1. whstl ◴[24 Jun 25 15:23 UTC] No.44367225[source]▶
With SMTP there are services who provide a list of malicious servers so that they can be blocked at the receiving end.

I wonder if this would work in reverse, having a standardised, automated protocol that allow providers like Cloudflare to notify upstream networks of attacks in real time, so malicious traffic can be blocked closer to the source.

Genuinely curious, I'm not an expert in low-level networking ops.