Re: [Amsn-devel] aMSN <= 0.96 remote DoS vulnerability

[Levent Kayan <levent () corehack org>]

On Sun, Apr 22, 2007 at 05:41:25PM +0200, Sebastian Rother wrote:
> On Sun, 22 Apr 2007 01:32:35 -0400
> kakaroto () kakaroto homelinux net (Youness Alaoui) wrote:
>
> > Hi,
> >  
> > I'm a developer and admin of the aMSN project, someone just sent me this link 
> > ( http://lists.grok.org.uk/pipermail/full-disclosure/2007-April/053912.html ).
> >  
> > I just grepped in the source code and that port (31337) is not used by aMSN, it could be a port used for a 
> > profile (as a locking system), in which case the port is randomly chosen each time, so this is probably just a 
> > fluke, he found the port of his current aMSN instance and used it. 
> >  
> > As I don't have more info, I can't really test this bug and find the real cause and fix it, so it would be nice 
> > to have more info about this. 
> >  
> > Seeing how the user replied on the "Vendor contacted?" tag, I wonder if I can get any more info on this matter.
> >  
> > Thanks,
> > KaKaRoTo
> >
> > _______________________________________________
> > Full-Disclosure - We believe in it.
> > Charter: http://lists.grok.org.uk/full-disclosure-charter.html
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31337 is just an example port! aMSN is binding an ephermal port after you've
started it. Just do a netstat -an and look for ephermal ports. If you get the
aMSN port you can connect to it and sending some characters and you'll get
replies by aMSN. 
If you send an '{' or '}' character to that amsn port, you'll notice
that aMSN is reporting an error message (amsn window). 
But if you going to send more than one character of '}' or '{' 
it will be killed. Yes, the whole client!

To "Ismail Soenmez": What about "DDoS"? Sending characters to that port in an
"infinite" loop is a DDoS for you? 
-- 
Name: Levent Kayan
E-Mail: levent () corehack org
GPG key: 
0xd6794965
Key fingerprint:
FD20 03C3 DD7F 51BB 224F  F11E 0855 23C8 D679 4965
Website:
http://www.corehack.org/

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