Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 6 Nov 1997 10:38:07 -0800 (PST)
From:      Archie Cobbs <archie@whistle.com>
To:        dnelson@slip.net (Dru Nelson)
Cc:        brandon@roguetrader.com, freebsd-isp@FreeBSD.ORG
Subject:   Re: Security problem/oversight with user PPP!
Message-ID:  <199711061838.KAA11072@bubba.whistle.com>
In-Reply-To: <Pine.GSO.3.96.971106092836.11993A-100000@slip-3> from Dru Nelson at "Nov 6, 97 09:30:38 am"

next in thread | previous in thread | raw e-mail | index | archive | help
Dru Nelson writes:
> > >  I agreee, it shouldn't be on by default. It is good, though, when
> > >  you want to work on the PPP client on the far end when getting
> > >  things working.
> > 
> > Doesn't completely fill the hole... :-)
> > 
> > I can still take a UNIX machine on the same network as yours,
> > disable my loopback interface, and set a route to 127.0.0.1
> > via your machine, and then telnet to it.
> > 
>  
>   Hi, where was I 'fill the hole'. If it is off, you can't telnet to 3000?
> 
>   Are you saying that Freebsd has a security hole where it allows 
>   ip with a source of 127.0.0.1.  When it replies for that SYN for
>   telnet, why would it go back to your machine?

Sorry, I was referring to the "fix" that just binds to
127.0.0.1 port 3000 (instead of INADDR_ANY) for the telnet thing.

Whether it's a security hole or a feature depends on how you
look at it. FreeBSD is working as designed. But yes, if I send
a packet to your 127.0.0.1, it will have my (normal) source
address.. so the response to my SYN comes back to me, etc.

-Archie

___________________________________________________________________________
Archie Cobbs   *   Whistle Communications, Inc.  *   http://www.whistle.com



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199711061838.KAA11072>