WebSocket-related DoS

[maximcherny]

Hi,

Logging here as suggested by @xntrik. I am the original reporter of the DoS issue fixed by 4db4354.

Open file limit-based DoS is still possible when the server is flooded with websocket connections. A basic test on OS X...

On the client:

var ws = [];
for (var i = 1; i <= 1000; i++) 
{ 
    ws.push(new WebSocket('ws://127.0.0.1:61985/'));
}

On the server:

Internal server error
Too many open files - stty gfmt1:cflag=4b00:iflag=6a02:lflag=200005cb:oflag=3:discard=f:dsusp=19:eof=4:eol=ff:eol2=ff:erase=7f:intr=3:kill=15:lnext=16:min=1:quit=1c:reprint=12:start=11:status=14:stop=13:susp=1a:time=0:werase=17:ispeed=9600:ospeed=9600 (Errno::EMFILE)

[xntrik]

Thanks @maximcherny for the post. Team: I wanted Maxim to post this so I didn't have to continue relaying things via email :P

[wadealcorn]

Thanks all

[radoen]

Hi all,
sorry for the delay. I've checked the issue, I think it's not something
strictly related to the beef's websocket function but it's more probably
related with the limit for opened fd's on OSX. I've reproduced the problem
on Debian 8, an attacker can DoS our server by opening a lot of ws
connection, beef don't crash on debian but we can't open more fd so we are
basically down...

https://cloud.githubusercontent.com/assets/1493320/7544148/e23f7aee-f5ca-11e4-86a1-34bc02b80e43.png

Make sense?
I'll try to check on my friend's mac this week-end

Cheers Graziano

2015-05-07 0:34 GMT+02:00 Wade Alcorn notifications@github.com:

Thanks all

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#1113 (comment).

[antisnatchor]

Any news on this @radoen ? let us know ;-) thanks

[antisnatchor]

I don't have this issue, confirmed as Radoen said. Closing this.