Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 22 Jun 1997 21:46:04 -0700 (PDT)
From:      Jim Shankland <jas@flyingfox.com>
To:        danny@panda.hilink.com.au
Cc:        freebsd-security@FreeBSD.ORG
Subject:   Re: Simple TCP service can hang a system (fwd)
Message-ID:  <199706230446.VAA19002@biggusdiskus.flyingfox.com>

next in thread | raw e-mail | index | archive | help
Daniel O'Callaghan <danny@panda.hilink.com.au> quotes Willy TARREAU
<tarreau@AEMIAIF.IBP.FR> as follows:

> I've noticed that inetd doesn't check the source port for the request
> to UDP simple services (echo, time, chargen, daytime).
> 
> This means it is possible to build a packet which will look like it
> comes from one of these ports, to one of these ports. In this case,
> each UDP response from the simple service will generate a new request
> to the source port and the system or network can be quickly
> overloaded.

Of course, I don't see any reason to make these services available
across administrative boundaries (or zones of trust), anyway.  They're
routinely firewalled off anywhere I've been around :-).

Jim Shankland
Flying Fox Computer Systems, Inc.



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199706230446.VAA19002>