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Slow Loris Attack

This is one of the coolest types of denial of service I’ve seen and I had to make a short post on it.

Usually with a denial of service attack, you need a fast internet connection to make a server unusable or where they are limiting speed per machine or you need a lot more, you need to DDoS with a botnet preferably personal computers (for residential IPs).

A slow loris attack in comparison does not require a fast internet connection. A slow loris attack is a protocol attack (layer 7) and is very easy to use. Your requests of resources on a page can be done so slowly with many connections that it can bring a server down. There are some mitigation such as timeouts but if you don’t send no data and instead send some data but very slowly, it can be difficult for a server to determine if you are performing an attack or if you just have a really slow internet connection. As long as you trick the server into thinking this, it makes the server unreachable for others. You can run many connections at the same time and if they have a limit per IP for that server, you can do the same across your botnet.

This type of attack works better on some web servers than others (best on apache I believe) and is more difficult if they are using something such as cloudflare but it is still very cool. There are other interesting attacks too such as R-U-Dead-Yet if you want to look into them more.

P.S. A slow loris is very cute.