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UDP Flooder in C

Yesterday we where still working on some attacks on our  bench test  and we tried some exploits on IP phones
that we found on the internet. Most of them where making DOS or DDOS on the phones,
this means that the phones were basically freezing.  Then we made some modification to a C UDP flooder code that I had from a few years.

The code is basically sending UDP on random ports to a specific address with a random source  … and only working on linux.
the code helped us to stop the connection between the 2 phones.


The code sends UDP packets to a phone wich tries to answer by pings and become unavailable for all the other network devices. Since the UDP packets are crafted with random addresses (or predefined addresses … the phone replies with pings to these addresses and thus not to your computer)

We also discovered that when the connection between the 2 phones is established the IP phone were not affected.

The code can be found below  or on my github repo

The code is working well, and can annoy people without damaging  the phone.
you can easily compile it with the following command :

and run it with

if everything is working you should see

this is appearing during the run time.

we tested it on 7940 phones from cisco and it was working pretty well.

Btw : this code can run against multiple network equipments, it was not dedicated to IP phones so I guess some kind of DOS or DDOS would be possible  by running it on multiple machines.

Have fun.

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