Hacker News Reader

Comment by agnokapathetic | Hacker News Reader

After RSnake introduced slowloris in 2009, it’s been something of a minor miracle that L7 attacks have stayed as rare as they have until now. Don’t understand why SYN Floods have been the preferred way to DDoS until recently-they’ve been obsolete for nearly a decade..

View on HN

Dumb packet flood is easy.

L7 DoS requires more sophistication, because the attack code needs to stateful (iow. establish sessions) and craft requests that are better targeted. These in turn require either real effort or tools that reduce the effort.

All of this implies one thing: packet flood mitigation has finally become so ubiquitious that dumb flooding is no longer lucrative. So one could say that due to lack of low-hanging fruit the attackers are now moving up in the value chain.

>they’ve been obsolete for nearly a decade..

It's almost like the entire Internet doesn't immediately handle every vulnerability as soon as it comes out...

You’d be surprised to learn that most of the targets are using the same small group of cdns, mostly Cloudflare and a few more.

Handling these attacks is difficult and a cdn is cheap.

Synfloods are really easy to accomplish comparatively. That said with the size and sophistication of the botnets these days I suspect that'll start to change to higher level attacks against services.

Slowiris doesn’t affect an async server like nginx, which Cloudflare deploys.

You need to configure it properly, though, otherwise you can still easily hit the open file descriptors limits in the OS.

Must be hard to adjust to different light with a slowiris.

They still work.

If it's the most effective tool for the job, it's not obsolete.

Reply on news.ycombinator.com